unsigned integer constraint (uint)

LANGUAGE.md

@@ -18,11 +18,13 @@ roadmap and milestone history.
 - `hide` makes any named top-level declaration file-local; declarations are public by default,
   leading underscores are ordinary identifier characters, and imports are always file-local
 - relative `.h` imports as synthetic C header package namespaces
+- native `name test { ... }` declarations with implicit fallible-void results, plus anonymous
+  transitive `test import "..."` discovery used only by test builds
 - root `main` validation with trap executable recovery for missing or unusable entry points
 
 ### scalar, aggregate, and pointer types
 
-- exact-width integers, `isize`, `usize`, `f32`, `f64`, `bool`, `void`, `anyopaque`, and contextual `int`, `float`, and `range` constraints
+- exact-width integers, concrete pointer-sized `isize` / `usize`, `f32`, `f64`, `bool`, `void`, and `anyopaque`; contextual `int` accepts the whole integer family, while `uint` accepts only unsigned native and target-classified C integers
 - target-dependent C scalar primitives from `c_char` through `c_longdouble`, kept semantically distinct from native scalars
 - contextual integer/float/character literals, backward type-demand inference through names and arithmetic, and compile-time folding for numeric constant expressions
 - strict numeric conversion by default, widening where valid, C scalar coercions at C boundaries, and explicit scalar keyword casts such as `i32(x)` / `c_float(x)`
@@ -42,16 +44,17 @@ roadmap and milestone history.
 
 #### native record constraint fields
 
-A direct `int`, `float`, or `range` field in a named native struct or union is a
+A direct `int`, `uint`, `float`, or `range` field in a named native struct or union is a
 program-wide constraint, not per-value polymorphism. Before record layout, all reachable keyed
 constructors, field assignments, and concrete uses of field reads contribute demands and the field
 resolves once to one concrete runtime type. Compatible scalar demands widen normally. Integer
 literals remain provisional until inference settles, so a later `usize` use can resolve an `int`
 field to `usize`; otherwise literal-only `int` fields use the widest smallest-signed type required,
-and literal-only `float` fields use `f64`.
+literal-only `uint` fields use the widest smallest-unsigned type required, and literal-only `float`
+fields use `f64`.
 
 An undemanded field or incompatible demands are errors. This inference applies only to direct
-fields of named native records. `c_struct` fields, nested constraints such as `[]int`, and fields in
+fields of named native records. `c_struct` fields, nested constraints such as `[]int` / `[]uint`, and fields in
 anonymous generated records still require concrete runtime types.
 
 #### keyword member names
@@ -180,6 +183,8 @@ as `math.divfloor(a, b)` resolve to ordinary functions.
 - `std/io` explicit `Io` capabilities, provider-bound `Reader`/`Writer` handles, existing-file open/close operations, allocation-free `write_all`, and comptime-expanded writer-first `print`; formatting supports natural `{}`, byte `{s}`, decimal `{d}`, integer `{b}` / `{o}` / `{x}` / `{X}`, byte-character `{c}`, scientific float `{e}`, and `{{` / `}}`, with malformed formats and incompatible tuple fields rejected at comptime
 - entry points are either `main func() ...` or `main func(init process.Init) ...`; `std/process.Init` carries startup capabilities, currently only `io`, while the system provider remains hidden inside `std/io`
 - `std/debug.print` is an allocation-free, failure-ignoring stderr escape hatch independent of `process.Init`
+- `std/testing` supplies fallible `expect` and expected-first `expect_equal`; direct calls through
+  an alias of exactly `@std/testing` receive compiler-injected source locations
 
 ### compiler behavior
 
@@ -188,6 +193,8 @@ as `math.divfloor(a, b)` resolve to ordinary functions.
 - static, eager runtime, mutable runtime, and deferred problematic globals with cycle diagnostics
 - demand-driven LLVM declarations for referenced foreign functions
 - root `main` may be parameterless or accept canonical `@std/process Init`; the generated C entry point obtains the hidden system I/O provider and constructs the init value
+- `brolang test [root]` reuses `build.bro`, discovers only explicit test-import edges, skips the
+  application entry point, and runs tests sequentially while continuing after assertion failures
 - replaceable dynamically loaded libclang C-import backend
 - C-header import caching by canonical path, target, include paths, and defines
 

README.md

@@ -73,6 +73,27 @@ linker inputs) and, like those flags, their paths are relative to the invocation
 directory. Lists take the address of an array literal; empty lists are written
 `&[]`. See `examples/build/` for runnable projects.
 
+Projects can declare tests directly and run them with `brolang test [root]`.
+The command reads the same `build.bro`, writes `build/<name>-test`, and reuses
+its C link inputs, libraries, include paths, and defines.
+
+```bro
+math :: import "../math"
+testing :: import "@std/testing"
+
+test import "../math"
+
+addition test {
+	try testing.expect(math.add(20, 22) == 42)
+	try testing.expect_equal(42, math.add(20, 22))
+}
+```
+
+`test import` discovers tests transitively without creating a namespace;
+calling package code still requires an ordinary import. Ordinary imports do
+not discover dependency tests. Assertions report their source location, a
+failure ends only the current test, and the runner continues with the suite.
+
 Relative `.h` imports create synthetic package namespaces backed by libclang:
 
 ```bro

TODO.md

@@ -897,6 +897,22 @@
   - `tag!` reads or folds a tagged union discriminant, while `tagname!` turns a comptime-known enum
     value into its immutable field-name string
 
+41. native test framework (implemented; v1)
+  - `name test { ... }` declares an implicit `void ! testing.Error` test omitted from executable builds
+  - anonymous `test import` edges discover dependency tests transitively; ordinary imports remain
+    separate namespaces and never discover tests
+  - direct `@std/testing` `expect` and expected-first `expect_equal` calls inject their source locations
+  - `brolang test` reuses `build.bro`, runs tests sequentially, continues after assertion failures,
+    prints a summary, and returns failure when a test fails or traps
+  - filtering, skipping, fixtures, snapshots, parallelism, isolation, allocators, and more assertion
+    families remain deferred
+
+42. unsigned integer constraint (implemented)
+  - `uint` is the unsigned subset constraint while `int` remains the whole integer family
+  - literal-only values choose the smallest fitting `u8`, `u16`, `u32`, or `u64`
+  - native unsigned scalars and target-classified unsigned C scalars satisfy the constraint
+  - `isize` and `usize` remain concrete pointer-sized types
+
 ## A word on unchecked casts
 
 For casts that bypass safety checks, Honey provides builtin functions:

compiler/ast/ast.odin

@@ -227,6 +227,7 @@ Function :: struct {
 	c_abi:      bool,
 	imported:   bool,
 	generated:  bool,
+	test:       bool,
 	file_hidden: bool,
 	has_body:   bool,
 	variadic:   bool,
@@ -276,6 +277,7 @@ Import :: struct {
 	target:     Package_Id,
 	valid:      bool,
 	used:       bool,
+	test_only:  bool,
 	diagnostic: source.Diagnostic_Id,
 }
 
@@ -310,9 +312,15 @@ Package :: struct {
 	path:      string,
 	name:      symbol.Id,
 	available: bool,
+	test:      bool,
 	kind:      Package_Kind,
 }
 
+Compile_Mode :: enum u8 {
+	Executable,
+	Test,
+}
+
 Package_Kind :: enum u8 {
 	Native,
 	C_Header,

compiler/build.odin

@@ -43,26 +43,7 @@ destroy_build_config :: proc(cfg: ^BuildConfig) {
 	delete(cfg.c_options.defines)
 }
 
-// run_build implements `brolang build [root]`: it loads and type-checks
-// `root/build.bro`, reads its `config` constant, and compiles the program
-// package the config names. build.bro is only checked (never lowered/emitted),
-// so the config is read straight from the HIR.
-run_build :: proc(root: string) -> int {
-	project_root := root
-	owns_project_root := false
-	if len(project_root) == 0 {
-		found_root, found := find_build_root()
-		if !found {
-			fmt.eprintln("brolang build: could not find build.bro in the current directory or any parent")
-			return 2
-		}
-		project_root = found_root
-		owns_project_root = true
-	}
-	defer if owns_project_root {
-		delete(project_root)
-	}
-
+load_build_config :: proc(project_root: string) -> (BuildConfig, bool) {
 	sources := source.init_store()
 	defer source.destroy_store(&sources)
 	diagnostics := source.init_store_diagnostics(&sources)
@@ -73,7 +54,7 @@ run_build :: proc(root: string) -> int {
 	arena: vmem.Arena
 	if err := vmem.arena_init_growing(&arena); err != nil {
 		fmt.eprintln("failed to initialize build arena:", err)
-		return 2
+		return {}, false
 	}
 	defer vmem.arena_destroy(&arena)
 	a := vmem.arena_allocator(&arena)
@@ -82,7 +63,7 @@ run_build :: proc(root: string) -> int {
 	if !loaded {
 		source.print_all(&diagnostics)
 		fmt.eprintln("failed to load build root:", project_root)
-		return 2
+		return {}, false
 	}
 	// check needs no `main`: it synthesizes a trap main and emits one benign
 	// "missing main" diagnostic, which is expected for build.bro. Suppress that
@@ -90,10 +71,32 @@ run_build :: proc(root: string) -> int {
 	hir_module := checker.check(&ast_module, &diagnostics, &symbols, target.DEFAULT, a)
 	if build_bro_has_errors(&diagnostics) {
 		source.print_all(&diagnostics)
+		return {}, false
+	}
+	return extract_build_config(&hir_module, &symbols)
+}
+
+project_root_for_command :: proc(root, command: string) -> (string, bool, bool) {
+	if len(root) > 0 {
+		return root, false, true
+	}
+	project_root, found := find_build_root()
+	if !found {
+		fmt.eprintfln("brolang %s: could not find build.bro in the current directory or any parent", command)
+		return "", false, false
+	}
+	return project_root, true, true
+}
+
+// run_build implements `brolang build [root]`: it reads build.bro and compiles
+// the configured program package.
+run_build :: proc(root: string) -> int {
+	project_root, owned, found := project_root_for_command(root, "build")
+	if !found {
 		return 2
 	}
-
-	cfg, ok := extract_build_config(&hir_module, &symbols)
+	defer if owned {delete(project_root)}
+	cfg, ok := load_build_config(project_root)
 	if !ok {
 		return 2
 	}
@@ -109,6 +112,48 @@ run_build :: proc(root: string) -> int {
 	return compile_package(program, output, cfg.link_arguments, target.DEFAULT, cfg.c_options, project_root)
 }
 
+run_tests :: proc(root: string) -> int {
+	project_root, owned, found := project_root_for_command(root, "test")
+	if !found {
+		return 2
+	}
+	defer if owned {delete(project_root)}
+	cfg, ok := load_build_config(project_root)
+	if !ok {
+		return 2
+	}
+	defer destroy_build_config(&cfg)
+
+	program := filepath.join({project_root, cfg.source_dir})
+	defer delete(program)
+	test_name := fmt.aprintf("%s-test", cfg.output_name)
+	defer delete(test_name)
+	output, output_ok := build_output_path(project_root, test_name)
+	if !output_ok {
+		return 2
+	}
+	defer delete(output)
+	status := compile_package(
+		program, output, cfg.link_arguments, target.DEFAULT, cfg.c_options, project_root, .Test,
+	)
+	if status != 0 {
+		return status
+	}
+	state, stdout, stderr, err := os2.process_exec(
+		os2.Process_Desc{command=[]string{output}},
+		context.allocator,
+	)
+	defer delete(stdout)
+	defer delete(stderr)
+	if len(stdout) > 0 {fmt.print(string(stdout))}
+	if len(stderr) > 0 {fmt.eprint(string(stderr))}
+	if err != nil {
+		fmt.eprintln("failed to run test executable:", err)
+		return 2
+	}
+	return 0 if state.exit_code == 0 else 1
+}
+
 valid_output_name :: proc(name: string) -> bool {
 	return len(name) > 0 && name != "." && name != ".." &&
 	       !strings.contains(name, "/") && !strings.contains(name, "\\")

compiler/checker/checker.odin

@@ -501,7 +501,7 @@ write_type_label :: proc(checker: ^Checker, builder: ^strings.Builder, value: ty
 		strings.write_string(builder, "enum")
 	case .Alias, .Distinct, .Named:
 		write_type_label(checker, builder, item.child)
-	case .Invalid, .Void, .Anyopaque, .Int_Constraint, .Float_Constraint, .Range_Constraint, .Scalar:
+	case .Invalid, .Void, .Anyopaque, .Int_Constraint, .Uint_Constraint, .Float_Constraint, .Range_Constraint, .Scalar:
 		strings.write_string(builder, types.name(value))
 	}
 }
@@ -1052,6 +1052,26 @@ fits_i64 :: proc(value: i128) -> bool {
 	return fits_signed_type(value, types.I64)
 }
 
+fits_u64 :: proc(value: i128) -> bool {
+	return value >= 0 && value <= i128(0xffff_ffff_ffff_ffff)
+}
+
+constraint_integer_literal_type :: proc(constraint: types.Type, value: i128) -> types.Type {
+	if constraint == types.UINT {
+		return types.smallest_unsigned_for_literal(u64(value)) if fits_u64(value) else types.INVALID
+	}
+	return types.smallest_signed_for_literal(i64(value)) if fits_i64(value) else types.INVALID
+}
+
+constraint_recovery_type :: proc(checker: ^Checker, constraint: types.Type) -> types.Type {
+	switch constraint {
+	case types.UINT:  return types.U64
+	case types.FLOAT: return types.F64
+	case types.RANGE: return types.range(&checker.module.types, types.I64)
+	case:             return types.I64
+	}
+}
+
 type_from_syntax :: proc(
 	checker: ^Checker,
 	value: ast.Type_Syntax,
@@ -1386,9 +1406,20 @@ build_symbol_indexes :: proc(checker: ^Checker) {
 	}
 	slice.sort_by(checker.global_index, global_index_less)
 
-	checker.import_index = make([]Import_Index_Entry, len(checker.ast_module.imports), checker.allocator)
+	import_count := 0
+	for import_item in checker.ast_module.imports {
+		if !import_item.test_only {
+			import_count += 1
+		}
+	}
+	checker.import_index = make([]Import_Index_Entry, import_count, checker.allocator)
+	import_index := 0
 	for import_item, id in checker.ast_module.imports {
-		checker.import_index[id] = Import_Index_Entry{scope=import_item.file, name=import_item.alias, id=ast.import_id(id)}
+		if import_item.test_only {
+			continue
+		}
+		checker.import_index[import_index] = Import_Index_Entry{scope=import_item.file, name=import_item.alias, id=ast.import_id(id)}
+		import_index += 1
 	}
 	slice.sort_by(checker.import_index, import_index_less)
 }
@@ -2636,7 +2667,7 @@ call_arg_expected :: proc(checker: ^Checker, function: ast.Function, index: int)
 	declared := type_from_syntax(checker, function.params[index].type, function.pkg, function.file)
 	// A `float` param defaults to f64 so an integer-literal argument builds as a
 	// float constant (e.g. `f(3)` -> 3.0), mirroring `pi float = 3` for locals.
-	// `int`/`range` constraints have no single default and keep building naturally.
+	// Integer/range constraints keep building naturally from their literals.
 	if declared == types.FLOAT {
 		return types.F64
 	}
@@ -3613,13 +3644,21 @@ record_field_expr_candidate :: proc(
 	}
 	expr := checker.ast_module.exprs[expr_id]
 	constraint := checker.record_field_constraints[slot]
-	if constant := eval_integer_constant_in_context(checker, expr_id, pkg, file);
-	   constant.kind == .Value && fits_i64(constant.value) {
-		candidate := types.smallest_signed_for_literal(i64(constant.value))
-		if constraint == types.FLOAT {
-			candidate = types.F64
+	if !numeric_operand_is_open(checker, expr_id, locals, pkg, file) {
+		concrete := types.constraint_target(constraint, inferred, &checker.module.types)
+		if is_runtime_type(checker, concrete) {
+			return merge_record_field_demand(checker, slot, concrete, expr.span)
+		}
+	}
+	if constant := eval_integer_constant_in_context(checker, expr_id, pkg, file);
+	   constant.kind == .Value {
+		candidate := constraint_integer_literal_type(constraint, constant.value)
+		if constraint == types.FLOAT {
+			candidate = types.F64 if fits_i64(constant.value) else types.INVALID
+		}
+		if types.is_valid(candidate) {
+			return merge_record_field_default(checker, slot, candidate, expr.span)
 		}
-		return merge_record_field_default(checker, slot, candidate, expr.span)
 	}
 	if is_float_constant_expr(checker, expr_id) {
 		return merge_record_field_default(checker, slot, types.F64, expr.span)
@@ -3682,14 +3721,7 @@ finalize_record_field_inference :: proc(checker: ^Checker) {
 			)
 		}
 		if types.is_constraint(current) {
-			switch constraint {
-			case types.INT:
-				checker.module.types.fields[slot].type = types.I64
-			case types.FLOAT:
-				checker.module.types.fields[slot].type = types.F64
-			case types.RANGE:
-				checker.module.types.fields[slot].type = types.range(&checker.module.types, types.I64)
-			}
+			checker.module.types.fields[slot].type = constraint_recovery_type(checker, constraint)
 		}
 	}
 }
@@ -3988,7 +4020,7 @@ find_spec :: proc(
 }
 
 // specialized_param_type maps a parameter's declared type to its monomorphized
-// type for a given actual argument. A constraint param (`int`/`float`/`range`)
+// type for a given actual argument. A constraint param (`int`/`uint`/`float`/`range`)
 // resolves to the actual's family member (INVALID if out of family), so a call
 // passing an out-of-family argument fails to specialize and is rejected.
 specialized_param_type :: proc(
@@ -4415,14 +4447,16 @@ infer_expr :: proc(
 			if expr.kind != .Name || symbol.is_valid(expr.qualifier) || !static_name {
 				constant = eval_constant(checker, frame.expr)
 			}
-			if constant.kind == .Overflow || constant.kind == .Div_By_Zero ||
-			   (constant.kind == .Value && !fits_i64(constant.value)) {
+			if constant.kind == .Overflow || constant.kind == .Div_By_Zero {
 				last = types.I64
 				_ = pop(&stack)
 				continue
 			}
 			if constant.kind == .Value {
-				last = types.smallest_signed_for_literal(i64(constant.value))
+				last = constraint_integer_literal_type(frame.expected, constant.value)
+				if !types.is_valid(last) {
+					last = types.I64
+				}
 				_ = pop(&stack)
 				continue
 			}
@@ -5055,7 +5089,7 @@ infer_statements :: proc(
 			declared_local := resolve_inferred_array(checker, type_from_syntax(checker, statement.type, pkg, file), statement.expr)
 			value_type := types.INVALID
 			if !is_undefined_expr(checker, statement.expr) {
-				expected := declared_local if is_runtime_type(checker, declared_local) else types.INVALID
+				expected := declared_local if is_runtime_type(checker, declared_local) || declared_local == types.UINT else types.INVALID
 				value_type = infer_expr(checker, statement.expr, locals^[:], pkg, file, demanded, local_types, expected)
 				declared_local = resolve_inferred_array_from_type(checker, declared_local, value_type)
 			}
@@ -5071,7 +5105,8 @@ infer_statements :: proc(
 			const_val := i128(0)
 			if !is_runtime_type(checker, declared_local) && !is_undefined_expr(checker, statement.expr) {
 				constant := eval_integer_constant_in_context(checker, statement.expr, pkg, file)
-				if constant.kind == .Value && fits_i64(constant.value) {
+				if constant.kind == .Value &&
+				   (fits_i64(constant.value) || declared_local == types.UINT && fits_u64(constant.value)) {
 					open = true
 					const_val = constant.value
 				} else if is_float_constant_expr(checker, statement.expr) {
@@ -5112,11 +5147,25 @@ infer_statements :: proc(
 			expected_assignment := types.INVALID
 			if statement.target != ast.INVALID_EXPR {
 				expected_assignment = infer_expr(checker, statement.target, locals^[:], pkg, file, demanded, local_types)
+				target_expr := checker.ast_module.exprs[statement.target]
+				if target_expr.kind == .Name && !symbol.is_valid(target_expr.qualifier) {
+					if local_index, ok := find_infer_local_index(locals^[:], target_expr.name); ok &&
+					   locals^[local_index].declared == types.UINT {
+						expected_assignment = types.UINT
+					} else if global := find_global(checker, target_expr.name, pkg, file); global != ast.INVALID_GLOBAL {
+						ast_global := checker.ast_module.globals[global]
+						if type_from_syntax(checker, ast_global.type, ast_global.pkg, ast_global.file) == types.UINT {
+							expected_assignment = types.UINT
+						}
+					}
+				}
 			} else if statement.name != checker.sink_symbol {
 				if local_index, ok := find_infer_local_index(locals^[:], statement.name); ok {
-					expected_assignment = locals^[local_index].type
+					expected_assignment = types.UINT if locals^[local_index].declared == types.UINT else locals^[local_index].type
 				} else if global := find_global(checker, statement.name, pkg, file); global != ast.INVALID_GLOBAL {
-					expected_assignment = checker.global_types[global]
+					ast_global := checker.ast_module.globals[global]
+					declared_global := type_from_syntax(checker, ast_global.type, ast_global.pkg, ast_global.file)
+					expected_assignment = types.UINT if declared_global == types.UINT else checker.global_types[global]
 				}
 			}
 			value_type := infer_expr(checker, statement.expr, locals^[:], pkg, file, demanded, local_types, expected_assignment)
@@ -5419,7 +5468,7 @@ infer_spec_locals_and_result :: proc(
 	if function.pkg == 0 && function.name == checker.main_symbol && function.result == types.INT {
 		declared = types.I32
 	}
-	result_hint := declared if is_runtime_type(checker, declared) else types.INVALID
+	result_hint := declared if is_runtime_type(checker, declared) || declared == types.UINT else types.INVALID
 
 	locals: [dynamic]Infer_Local
 	locals.allocator = checker.allocator
@@ -5604,7 +5653,7 @@ open_const_default_type :: proc(
 		if index, ok := find_infer_local_index(locals, expr.name); ok {
 			local := locals[index]
 			if local.open_const {
-				return types.smallest_signed_for_literal(i64(local.const_value))
+				return constraint_integer_literal_type(local.declared, local.const_value)
 			}
 			if local.open_float {
 				return types.F64
@@ -5622,7 +5671,9 @@ open_const_default_type :: proc(
 		return types.INVALID
 	}
 	if checker.global_open_const[index] {
-		return types.smallest_signed_for_literal(i64(checker.global_const_value[index]))
+		ast_global := checker.ast_module.globals[global]
+		declared := type_from_syntax(checker, ast_global.type, ast_global.pkg, ast_global.file)
+		return constraint_integer_literal_type(declared, checker.global_const_value[index])
 	}
 	if checker.global_open_float[index] {
 		return types.F64
@@ -5888,7 +5939,8 @@ infer_all :: proc(checker: ^Checker) {
 			}
 		}
 		constant := eval_integer_constant_in_context(checker, global.expr, global.pkg, global.file)
-		if constant.kind == .Value && fits_i64(constant.value) {
+		if constant.kind == .Value &&
+		   (fits_i64(constant.value) || declared == types.UINT && fits_u64(constant.value)) {
 			checker.global_open_const[index] = true
 			checker.global_const_value[index] = constant.value
 		} else if is_float_constant_expr(checker, global.expr) {
@@ -5936,7 +5988,7 @@ infer_all :: proc(checker: ^Checker) {
 				type_from_syntax(checker, global.type, global.pkg, global.file),
 				global.expr,
 			)
-			expected := declared if is_runtime_type(checker, declared) else types.INVALID
+			expected := declared if is_runtime_type(checker, declared) || declared == types.UINT else types.INVALID
 			inferred := infer_expr(checker, global.expr, nil, global.pkg, global.file, expected=expected)
 			if resolved := resolve_inferred_array_from_type(checker, declared, inferred);
 			   resolved != declared {
@@ -6009,7 +6061,8 @@ infer_all :: proc(checker: ^Checker) {
 						continue
 					}
 					if checker.global_open_const[index] {
-						checker.global_types[index] = types.smallest_signed_for_literal(i64(checker.global_const_value[index]))
+						declared := type_from_syntax(checker, global.type, global.pkg, global.file)
+						checker.global_types[index] = constraint_integer_literal_type(declared, checker.global_const_value[index])
 						defaulted = true
 					} else if checker.global_open_float[index] {
 						checker.global_types[index] = types.F64
@@ -6383,7 +6436,7 @@ build_constant_expr :: proc(
 		return invalid_hir_expr(checker, expr.span, id, recovery_type)
 	}
 	if constant.kind == .Overflow ||
-	   (!types.is_concrete_integer(expected) && !fits_i64(constant.value)) {
+	   (!types.is_concrete_integer(expected) && expected != types.UINT && !fits_i64(constant.value)) {
 		id := source.add(
 			checker.diagnostics,
 			expr.span,
@@ -6396,7 +6449,16 @@ build_constant_expr :: proc(
 	if constant.value >= 0 && constant.value <= i128(0xffff_ffff_ffff_ffff) {
 		value = transmute(i64)u64(constant.value)
 	}
-	result_type := types.smallest_signed_for_literal(value)
+	result_type := constraint_integer_literal_type(expected, constant.value)
+	if expected == types.UINT && !types.is_valid(result_type) {
+		id := source.addf(
+			checker.diagnostics,
+			expr.span,
+			"integer constant %d does not satisfy uint",
+			constant.value,
+		)
+		return invalid_hir_expr(checker, expr.span, id, types.U64)
+	}
 	if types.is_concrete_integer(expected) {
 		if !fits_integer_type(constant.value, expected, checker.target) {
 			id := source.addf(
@@ -12364,11 +12426,12 @@ build_globals :: proc(checker: ^Checker) {
 		if is_runtime_type(checker, declared) {
 			expected = declared
 		} else if constant := eval_integer_constant_in_context(checker, global.expr, global.pkg, global.file);
-		   constant.kind == .Value && fits_i64(constant.value) &&
+		   constant.kind == .Value &&
+		   (fits_i64(constant.value) || declared == types.UINT && fits_u64(constant.value)) &&
 		   is_runtime_type(checker, checker.global_types[global_index]) {
 			// Open integer constant: build against its demanded/defaulted type. Gated
 			// to the infer-side open-constant condition so out-of-range constants keep
-			// their original "exceeds signed i64 range" diagnostic.
+			// their original range diagnostic.
 			expected = checker.global_types[global_index]
 		} else if (is_float_constant_expr(checker, global.expr) ||
 		           is_numeric_arithmetic_expr(checker, global.expr)) &&
@@ -12390,6 +12453,18 @@ build_globals :: proc(checker: ^Checker) {
 				global_type = types.I64
 			}
 		}
+		if diagnostic == source.INVALID_DIAGNOSTIC && types.is_constraint(declared) &&
+		   !types.constraint_accepts(declared, global_type, &checker.module.types) {
+			diagnostic = source.addf(
+				checker.diagnostics,
+				global.span,
+				"could not resolve the '%s' constraint for global '%s'",
+				types.name(declared),
+				symbol_text(checker, global.name),
+			)
+			global_type = constraint_recovery_type(checker, declared)
+			expr = invalid_hir_expr(checker, global.span, diagnostic, global_type)
+		}
 		if !global.immutable && is_undefined_expr(checker, global.expr) {
 			diagnostic = source.add(
 				checker.diagnostics,
@@ -12874,7 +12949,7 @@ check :: proc(
 	main_template := find_template(&checker, checker.main_symbol, 0)
 	main_declarations := 0
 	for function in ast_module.functions {
-		if function.pkg == 0 && function.name == checker.main_symbol {
+		if !function.generated && function.pkg == 0 && function.name == checker.main_symbol {
 			main_declarations += 1
 		}
 	}
@@ -12917,7 +12992,7 @@ check :: proc(
 	delete(states, allocator)
 	propagate_problems(&checker)
 	for import_item in ast_module.imports {
-		if import_item.valid && !import_item.used {
+		if !import_item.test_only && import_item.valid && !import_item.used {
 			source.addf_warning(diagnostics, import_item.span, "unused import '%s'", symbol_text(&checker, import_item.alias))
 		}
 	}

compiler/compiler.odin

@@ -1,5 +1,6 @@
 package compiler
 
+import "./ast"
 import "./backend"
 import "./cimport"
 import "./checker"
@@ -34,6 +35,7 @@ compile_package :: proc(
 	selected := target.DEFAULT,
 	c_options := cimport.Options{},
 	project_root := "",
+	mode := ast.Compile_Mode.Executable,
 ) -> int {
 	sources := source.init_store()
 	defer source.destroy_store(&sources)
@@ -77,12 +79,18 @@ compile_package :: proc(
 		c_options,
 		selected,
 		project_root if len(project_root) > 0 else input_path,
+		mode,
 	)
 	if !loaded {
 		source.print_all(&diagnostics)
 		fmt.eprintln("failed to load root package directory:", input_path)
 		return 2
 	}
+	effective_root := project_root if len(project_root) > 0 else input_path
+	if !prepare_tests(&ast_module, &sources, &diagnostics, &symbols, mode, effective_root) {
+		source.print_all(&diagnostics)
+		return 1
+	}
 
 	// Generated C trampolines (for `static inline` imports) must be compiled and
 	// linked with the program. Write them out and add the source as a link input

compiler/lexer/lexer.odin

@@ -14,6 +14,7 @@ is_identifier_continue :: proc(value: byte) -> bool {
 
 keyword_kind :: proc(text: string) -> token.Kind {
 	switch text {
+	case "test":          return .Keyword_Test
 	case "func":          return .Keyword_Func
 	case "c_func":        return .Keyword_C_Func
 	case "struct":        return .Keyword_Struct
@@ -51,6 +52,7 @@ keyword_kind :: proc(text: string) -> token.Kind {
 	case "anyopaque":     return .Keyword_Anyopaque
 	case "bool":          return .Keyword_Bool
 	case "int":           return .Keyword_Int
+	case "uint":          return .Keyword_Uint
 	case "float":         return .Keyword_Float
 	case "range":         return .Keyword_Range
 	case "i8":            return .Keyword_I8

compiler/loader/loader.odin

@@ -26,6 +26,7 @@ State :: struct {
 	c_options:       cimport.Options,
 	selected:        target.Target,
 	project_root:    string,
+	mode:            ast.Compile_Mode,
 	record_identities: [dynamic]string,
 	record_types:      [dynamic]types.Type,
 	root_failed:     bool,
@@ -1130,7 +1131,42 @@ load_header :: proc(state: ^State, path: string, import_span: source.Span) -> as
 	return pkg_id
 }
 
-load_package :: proc(state: ^State, path: string, import_span: source.Span, is_root := false) -> ast.Package_Id {
+resolve_package_imports :: proc(state: ^State, pkg_id: ast.Package_Id) {
+	if int(pkg_id) >= len(state.module.packages) {
+		return
+	}
+	canonical := state.module.packages[pkg_id].path
+	import_count := len(state.module.imports)
+	for import_id in 0..<import_count {
+		import_item := state.module.imports[import_id]
+		if import_item.pkg != pkg_id || import_item.target != ast.INVALID_PACKAGE ||
+		   import_item.test_only && (state.mode != .Test || !state.module.packages[pkg_id].test) {
+			continue
+		}
+		if filepath.is_abs(import_item.path) {
+			state.module.imports[import_id].diagnostic = source.add(state.diagnostics, import_item.span, "absolute import paths are invalid")
+			state.module.imports[import_id].valid = false
+			state.module.imports[import_id].target = add_placeholder(state, import_item.path)
+			continue
+		}
+		target_path, target_ok := resolve_import_path(state, canonical, import_item.path)
+		target := load_header(state, target_path, import_item.span) if filepath.ext(import_item.path) == ".h" else
+		          load_package(state, target_path, import_item.span, include_tests=import_item.test_only)
+		state.module.imports[import_id].target = target
+		if !target_ok || target == ast.INVALID_PACKAGE || !state.module.packages[target].available {
+			state.module.imports[import_id].valid = false
+		}
+		delete(target_path, state.allocator)
+	}
+}
+
+load_package :: proc(
+	state: ^State,
+	path: string,
+	import_span: source.Span,
+	is_root := false,
+	include_tests := false,
+) -> ast.Package_Id {
 	canonical, ok := filepath.abs(path, state.allocator)
 	if !ok || !os.is_dir(path) {
 		if is_root {
@@ -1152,6 +1188,10 @@ load_package :: proc(state: ^State, path: string, import_span: source.Span, is_r
 		return id
 	}
 	if existing := find_package(state, canonical); existing != ast.INVALID_PACKAGE {
+		if include_tests && !state.module.packages[existing].test {
+			state.module.packages[existing].test = true
+			resolve_package_imports(state, existing)
+		}
 		delete(canonical, state.allocator)
 		return existing
 	}
@@ -1161,6 +1201,7 @@ load_package :: proc(state: ^State, path: string, import_span: source.Span, is_r
 		path=canonical,
 		name=symbol.intern(state.symbols, filepath.base(canonical)),
 		available=true,
+		test=state.mode == .Test && is_root || include_tests,
 	})
 	files, files_ok := read_package_files(state, canonical)
 	if !files_ok {
@@ -1204,26 +1245,7 @@ load_package :: proc(state: ^State, path: string, import_span: source.Span, is_r
 	}
 	os.file_info_slice_delete(files, state.allocator)
 
-	import_count := len(state.module.imports)
-	for import_id in 0..<import_count {
-		import_item := state.module.imports[import_id]
-		if import_item.pkg != pkg_id || import_item.target != ast.INVALID_PACKAGE {
-			continue
-		}
-		if filepath.is_abs(import_item.path) {
-			state.module.imports[import_id].diagnostic = source.add(state.diagnostics, import_item.span, "absolute import paths are invalid")
-			state.module.imports[import_id].valid = false
-			state.module.imports[import_id].target = add_placeholder(state, import_item.path)
-			continue
-		}
-		target_path, target_ok := resolve_import_path(state, canonical, import_item.path)
-		target := load_header(state, target_path, import_item.span) if filepath.ext(import_item.path) == ".h" else load_package(state, target_path, import_item.span)
-		state.module.imports[import_id].target = target
-		if !target_ok || target == ast.INVALID_PACKAGE || !state.module.packages[target].available {
-			state.module.imports[import_id].valid = false
-		}
-		delete(target_path, state.allocator)
-	}
+	resolve_package_imports(state, pkg_id)
 	return pkg_id
 }
 
@@ -1248,6 +1270,9 @@ declaration_conflicts :: proc(module: ^ast.Module, pkg: ast.Package_Id, file: as
 
 validate_imports :: proc(state: ^State) {
 	for import_item, import_id in state.module.imports {
+		if import_item.test_only {
+			continue
+		}
 		if !symbol.is_valid(import_item.alias) && import_item.target != ast.INVALID_PACKAGE {
 			state.module.imports[import_id].alias = state.module.packages[import_item.target].name
 		}
@@ -1287,7 +1312,7 @@ validate_imports :: proc(state: ^State) {
 
 find_type_import :: proc(module: ^ast.Module, file: ast.File_Id, alias: symbol.Id) -> ast.Import_Id {
 	for import_item, index in module.imports {
-		if import_item.file == file && import_item.alias == alias {
+		if !import_item.test_only && import_item.file == file && import_item.alias == alias {
 			return ast.import_id(index)
 		}
 	}
@@ -1879,6 +1904,7 @@ load :: proc(
 	c_options := cimport.Options{},
 	selected := target.DEFAULT,
 	project_root_path := "",
+	mode := ast.Compile_Mode.Executable,
 ) -> (ast.Module, bool) {
 	module := ast.init_module(allocator)
 	project_root_source := project_root_path if len(project_root_path) > 0 else root_path
@@ -1896,6 +1922,7 @@ load :: proc(
 		c_options=c_options,
 		selected=selected,
 		project_root=project_root,
+		mode=mode,
 	}
 	state.record_identities.allocator = allocator
 	state.record_types.allocator = allocator
@@ -1911,6 +1938,13 @@ load :: proc(
 	if root != ast.Package_Id(0) && root != ast.INVALID_PACKAGE {
 		state.root_failed = true
 	}
+	if mode == .Test {
+		testing_path, testing_error := filepath.join({project_root, "std", "testing"}, allocator)
+		if testing_error == nil {
+			_ = load_package(&state, testing_path, source.Span{})
+			delete(testing_path, allocator)
+		}
+	}
 	validate_imports(&state)
 	validate_declaration_aliases(&state)
 	resolve_enum_values(&state)

compiler/parser/parser.odin

@@ -146,7 +146,7 @@ invalid_expr :: proc(parser: ^Parser, span: source.Span, message: string) -> ast
 
 is_type_token :: proc(kind: token.Kind) -> bool {
 	#partial switch kind {
-	case .Keyword_Int, .Keyword_Float, .Keyword_Range, .Keyword_I8, .Keyword_I16, .Keyword_I32, .Keyword_I64,
+	case .Keyword_Int, .Keyword_Uint, .Keyword_Float, .Keyword_Range, .Keyword_I8, .Keyword_I16, .Keyword_I32, .Keyword_I64,
 	     .Keyword_U8, .Keyword_U16, .Keyword_U32, .Keyword_U64,
 	     .Keyword_Isize, .Keyword_Usize, .Keyword_F32, .Keyword_F64,
 	     .Keyword_C_Char, .Keyword_C_Schar, .Keyword_C_Uchar,
@@ -280,6 +280,9 @@ parse_type_atom :: proc(parser: ^Parser) -> ast.Type_Syntax {
 	case .Keyword_Int:
 		advance(parser)
 		return types.INT
+	case .Keyword_Uint:
+		advance(parser)
+		return types.UINT
 	case .Keyword_Float:
 		advance(parser)
 		return types.FLOAT
@@ -774,7 +777,7 @@ parse_integer_magnitude :: proc(text: string) -> (u64, bool) {
 parse_primary :: proc(parser: ^Parser, nesting: int) -> ast.Expr_Id {
 	tok := current(parser)
 	#partial switch tok.kind {
-	case .Keyword_Int, .Keyword_Float, .Keyword_Range, .Keyword_Void, .Keyword_Anyopaque, .Keyword_Bool:
+	case .Keyword_Int, .Keyword_Uint, .Keyword_Float, .Keyword_Range, .Keyword_Void, .Keyword_Anyopaque, .Keyword_Bool:
 		start := tok
 		target := parse_type_atom(parser)
 		return add_expr(parser, ast.Expr{
@@ -3002,7 +3005,7 @@ decode_multiline_string :: proc(parser: ^Parser, tok: token.Token) -> string {
 	return fmt.aprintf("%s", strings.to_string(builder), allocator=parser.module.allocator)
 }
 
-parse_import :: proc(parser: ^Parser, alias: token.Token, start: token.Token) {
+parse_import :: proc(parser: ^Parser, alias: token.Token, start: token.Token, test_only := false) {
 	skip_newlines(parser)
 	path_token := current(parser)
 	if path_token.kind != .String {
@@ -3018,6 +3021,7 @@ parse_import :: proc(parser: ^Parser, alias: token.Token, start: token.Token) {
 			file=parser.file,
 			target=ast.INVALID_PACKAGE,
 			valid=false,
+			test_only=test_only,
 			diagnostic=source.INVALID_DIAGNOSTIC,
 		})
 		_ = finish_statement(parser)
@@ -3033,13 +3037,45 @@ parse_import :: proc(parser: ^Parser, alias: token.Token, start: token.Token) {
 		file=parser.file,
 		target=ast.INVALID_PACKAGE,
 		valid=true,
+		test_only=test_only,
 		diagnostic=source.INVALID_DIAGNOSTIC,
 	})
 	_ = finish_statement(parser)
 }
 
+parse_test :: proc(parser: ^Parser, name: token.Token) {
+	advance(parser) // consume 'test'
+	skip_newlines(parser)
+	if current(parser).kind != .Left_Brace {
+		source.add(parser.diagnostics, current(parser).span, "expected '{' after test name")
+		_ = finish_statement(parser)
+		return
+	}
+	body := parse_block(parser)
+	append(&parser.module.functions, ast.Function{
+		span=span_from(name.span, previous(parser).span),
+		name=name.symbol,
+		pkg=parser.pkg,
+		file=parser.file,
+		test=true,
+		has_body=true,
+		result=types.VOID,
+		body=body,
+		diagnostic=source.INVALID_DIAGNOSTIC,
+	})
+}
+
 parse_top_level :: proc(parser: ^Parser) {
 	hide_token, file_hidden := allow(parser, .Keyword_Hide)
+	if current(parser).kind == .Keyword_Test && peek(parser).kind == .Keyword_Import {
+		if file_hidden {
+			source.add(parser.diagnostics, hide_token.span, "test imports cannot use 'hide'")
+		}
+		start := advance(parser)
+		advance(parser) // consume 'import'
+		parse_import(parser, token.Token{}, start, test_only=true)
+		return
+	}
 	if current(parser).kind == .Keyword_Import {
 		if file_hidden {
 			source.add(parser.diagnostics, hide_token.span, "imports are already file-local and cannot use 'hide'")
@@ -3058,6 +3094,13 @@ parse_top_level :: proc(parser: ^Parser) {
 		return
 	}
 	name := advance(parser)
+	if current(parser).kind == .Keyword_Test {
+		if file_hidden {
+			source.add(parser.diagnostics, hide_token.span, "test declarations cannot use 'hide'")
+		}
+		parse_test(parser, name)
+		return
+	}
 	if current(parser).kind == .Colon_Colon {
 		saved := parser.cursor
 		advance(parser)

compiler/testing.odin

@@ -0,0 +1,281 @@
+package compiler
+
+import "./ast"
+import "./lexer"
+import "./parser"
+import "./source"
+import "./symbol"
+import "./types"
+import "core:fmt"
+import "core:path/filepath"
+import "core:slice"
+import "core:strings"
+
+Test_Entry :: struct {
+	function:     ast.Function_Id,
+	package_path: string,
+	source_path:  string,
+	offset:       source.Offset,
+}
+
+test_entry_less :: proc(a, b: Test_Entry) -> bool {
+	if a.package_path != b.package_path {
+		return a.package_path < b.package_path
+	}
+	if a.source_path != b.source_path {
+		return a.source_path < b.source_path
+	}
+	return a.offset < b.offset
+}
+
+testing_package :: proc(module: ^ast.Module, project_root: string) -> ast.Package_Id {
+	path, err := filepath.join({project_root, "std", "testing"}, module.allocator)
+	if err != nil {
+		return ast.INVALID_PACKAGE
+	}
+	defer delete(path, module.allocator)
+	canonical, ok := filepath.abs(path, module.allocator)
+	if !ok {
+		return ast.INVALID_PACKAGE
+	}
+	defer delete(canonical, module.allocator)
+	for pkg, index in module.packages {
+		if pkg.path == canonical {
+			return ast.package_id(index)
+		}
+	}
+	return ast.INVALID_PACKAGE
+}
+
+source_file_id :: proc(module: ^ast.Module, id: source.Source_Id) -> ast.File_Id {
+	for file, index in module.files {
+		if file.source == id {
+			return ast.file_id(index)
+		}
+	}
+	return ast.INVALID_FILE
+}
+
+append_ast_expr :: proc(module: ^ast.Module, expr: ast.Expr) -> ast.Expr_Id {
+	id := ast.expr_id(len(module.exprs))
+	append(&module.exprs, expr)
+	return id
+}
+
+location_expr :: proc(
+	module: ^ast.Module,
+	sources: ^source.Store,
+	symbols: ^symbol.Table,
+	span: source.Span,
+	qualifier: symbol.Id,
+) -> ast.Expr_Id {
+	line, column := 1, 1
+	path := "<unknown>"
+	if int(span.file) < len(sources.items) {
+		file := &sources.items[span.file]
+		line, column = source.line_and_column(file, span.start)
+		path = file.path
+	}
+	string_index := u64(len(module.strings))
+	append(&module.strings, strings.clone(path, module.allocator))
+	file_expr := append_ast_expr(module, ast.Expr{
+		kind=.String, span=span, integer=string_index,
+		left=ast.INVALID_EXPR, right=ast.INVALID_EXPR,
+		diagnostic=source.INVALID_DIAGNOSTIC,
+	})
+	line_expr := append_ast_expr(module, ast.Expr{
+		kind=.Integer, span=span, integer=u64(line),
+		left=ast.INVALID_EXPR, right=ast.INVALID_EXPR,
+		diagnostic=source.INVALID_DIAGNOSTIC,
+	})
+	column_expr := append_ast_expr(module, ast.Expr{
+		kind=.Integer, span=span, integer=u64(column),
+		left=ast.INVALID_EXPR, right=ast.INVALID_EXPR,
+		diagnostic=source.INVALID_DIAGNOSTIC,
+	})
+	values := []ast.Expr_Id{file_expr, line_expr, column_expr}
+	names := []string{"file", "line", "column"}
+	fields := make([]ast.Expr_Id, 3, module.allocator)
+	for index in 0..<3 {
+		fields[index] = append_ast_expr(module, ast.Expr{
+			kind=.Keyed, span=span,
+			name=symbol.intern(symbols, names[index]),
+			left=values[index], right=ast.INVALID_EXPR,
+			diagnostic=source.INVALID_DIAGNOSTIC,
+		})
+	}
+	return append_ast_expr(module, ast.Expr{
+		kind=.Struct_Literal, span=span,
+		qualifier=qualifier,
+		name=symbol.intern(symbols, "SourceLocation"),
+		args=fields,
+		left=ast.INVALID_EXPR, right=ast.INVALID_EXPR,
+		diagnostic=source.INVALID_DIAGNOSTIC,
+	})
+}
+
+inject_assertion_locations :: proc(
+	module: ^ast.Module,
+	sources: ^source.Store,
+	symbols: ^symbol.Table,
+	testing_pkg: ast.Package_Id,
+) {
+	expect := symbol.intern(symbols, "expect")
+	expect_equal := symbol.intern(symbols, "expect_equal")
+	original_count := len(module.exprs)
+	for index in 0..<original_count {
+		expr := &module.exprs[index]
+		if expr.kind != .Call || expr.intrinsic || !symbol.is_valid(expr.qualifier) ||
+		   (expr.name != expect && expr.name != expect_equal) {
+			continue
+		}
+		file := source_file_id(module, expr.span.file)
+		matched := false
+		for import_item in module.imports {
+			if !import_item.test_only && import_item.file == file &&
+			   import_item.alias == expr.qualifier && import_item.target == testing_pkg {
+				matched = true
+				break
+			}
+		}
+		if !matched {
+			continue
+		}
+		location := location_expr(module, sources, symbols, expr.span, expr.qualifier)
+		args := make([]ast.Expr_Id, len(expr.args)+1, module.allocator)
+		copy(args, expr.args)
+		args[len(expr.args)] = location
+		delete(expr.args, module.allocator)
+		expr.args = args
+	}
+}
+
+write_brolang_string :: proc(builder: ^strings.Builder, value: string) {
+	for byte_value in transmute([]byte)value {
+		if byte_value == '\\' || byte_value == '"' {
+			strings.write_byte(builder, '\\')
+		}
+		strings.write_byte(builder, byte_value)
+	}
+}
+
+append_runner :: proc(
+	module: ^ast.Module,
+	sources: ^source.Store,
+	diagnostics: ^source.Diagnostics,
+	symbols: ^symbol.Table,
+	testing_pkg: ast.Package_Id,
+	tests: []Test_Entry,
+) {
+	builder := strings.builder_make(module.allocator)
+	defer strings.builder_destroy(&builder)
+	strings.write_string(&builder, "main func() i32 {\n\tfailed i32 = 0\n")
+	for entry, index in tests {
+		test_id := entry.function
+		test := module.functions[test_id]
+		pkg := module.packages[test.pkg]
+		alias := fmt.tprintf("__brolang_test_%d", index)
+		name := fmt.tprintf("%s.%s", filepath.base(pkg.path), symbol.resolve(symbols, test.name))
+		strings.write_string(&builder, "\tif (!__brolang_testing.run(\"")
+		write_brolang_string(&builder, name)
+		fmt.sbprintf(&builder, "\", %s.%s)) ", alias, symbol.resolve(symbols, test.name))
+		strings.write_string(&builder, "{\n\t\tfailed += 1\n\t}\n")
+	}
+	fmt.sbprintf(&builder, "\t__brolang_testing.summary(%d - failed, failed)\n", len(tests))
+	strings.write_string(&builder, "\tif (failed != 0) return 1\n\treturn 0\n}\n")
+
+	runner_text := strings.to_string(builder)
+	source_id := source.add_source(sources, "<brolang-test-runner>", runner_text)
+	file_id := ast.file_id(len(module.files))
+	append(&module.files, ast.File{source=source_id, pkg=0})
+	stream := lexer.lex(&sources.items[source_id], diagnostics, symbols, module.allocator)
+	defer delete(stream.items)
+	parser.parse_into(&stream, &sources.items[source_id], diagnostics, module, 0, file_id)
+
+	append(&module.imports, ast.Import{
+		alias=symbol.intern(symbols, "__brolang_testing"),
+		path=strings.clone("@std/testing", module.allocator),
+		pkg=0, file=file_id, target=testing_pkg,
+		valid=true, used=true,
+		diagnostic=source.INVALID_DIAGNOSTIC,
+	})
+	for entry, index in tests {
+		test_id := entry.function
+		test := module.functions[test_id]
+		append(&module.imports, ast.Import{
+			alias=symbol.intern(symbols, fmt.tprintf("__brolang_test_%d", index)),
+			path=strings.clone(module.packages[test.pkg].path, module.allocator),
+			pkg=0, file=file_id, target=test.pkg,
+			valid=true, used=true,
+			diagnostic=source.INVALID_DIAGNOSTIC,
+		})
+	}
+}
+
+prepare_tests :: proc(
+	module: ^ast.Module,
+	sources: ^source.Store,
+	diagnostics: ^source.Diagnostics,
+	symbols: ^symbol.Table,
+	mode: ast.Compile_Mode,
+	project_root: string,
+) -> bool {
+	if mode == .Executable {
+		for &function in module.functions {
+			if !function.test {
+				continue
+			}
+			function.generated = true
+			for &import_item in module.imports {
+				if !import_item.test_only && import_item.file == function.file {
+					import_item.used = true
+				}
+			}
+		}
+		return true
+	}
+
+	testing_pkg := testing_package(module, project_root)
+	if testing_pkg == ast.INVALID_PACKAGE {
+		source.add(diagnostics, source.Span{}, "test builds require @std/testing")
+		return false
+	}
+	error_type := types.find_named(
+		&module.type_store,
+		u32(testing_pkg),
+		u32(symbol.intern(symbols, "Error")),
+	)
+	if !types.is_enum(error_type, &module.type_store) {
+		source.add(diagnostics, source.Span{}, "@std/testing must declare Error as an enum")
+		return false
+	}
+
+	tests: [dynamic]Test_Entry
+	tests.allocator = module.allocator
+	defer delete(tests)
+	main_name := symbol.intern(symbols, "main")
+	for &function, index in module.functions {
+		if function.test {
+			if int(function.pkg) < len(module.packages) && module.packages[function.pkg].test {
+				function.result = types.VOID
+				function.error = error_type
+				file := module.files[function.file]
+				append(&tests, Test_Entry{
+					function=ast.function_id(index),
+					package_path=module.packages[function.pkg].path,
+					source_path=sources.items[file.source].path,
+					offset=function.span.start,
+				})
+			} else {
+				function.generated = true
+			}
+		} else if function.pkg == 0 && function.name == main_name {
+			function.generated = true
+		}
+	}
+
+	slice.sort_by(tests[:], test_entry_less)
+	inject_assertion_locations(module, sources, symbols, testing_pkg)
+	append_runner(module, sources, diagnostics, symbols, testing_pkg, tests[:])
+	return true
+}

compiler/token/token.odin

@@ -50,6 +50,7 @@ Kind :: enum u8 {
 	Right_Brace,
 	Comma,
 	Pipe,
+	Keyword_Test,
 	Keyword_Func,
 	Keyword_C_Func,
 	Keyword_Struct,
@@ -87,6 +88,7 @@ Kind :: enum u8 {
 	Keyword_Anyopaque,
 	Keyword_Bool,
 	Keyword_Int,
+	Keyword_Uint,
 	Keyword_Float,
 	Keyword_Range,
 	Keyword_I8,
@@ -118,7 +120,7 @@ Kind :: enum u8 {
 }
 
 is_keyword :: proc(kind: Kind) -> bool {
-	return kind >= .Keyword_Func && kind <= .Keyword_C_Longdouble
+	return kind >= .Keyword_Test && kind <= .Keyword_C_Longdouble
 }
 
 Token :: struct {

compiler/types/types.odin

@@ -44,6 +44,7 @@ BOOL :: Type(29)
 FLOAT :: Type(30)
 RANGE :: Type(31)
 ANYOPAQUE :: Type(32)
+UINT :: Type(33)
 
 DYNAMIC_START :: Type(64)
 
@@ -59,6 +60,7 @@ Kind :: enum u8 {
 	Void,
 	Anyopaque,
 	Int_Constraint,
+	Uint_Constraint,
 	Float_Constraint,
 	Range_Constraint,
 	Scalar,
@@ -595,6 +597,8 @@ kind :: proc(value: Type, store: ^Store = nil) -> Kind {
 		return .Anyopaque
 	case INT:
 		return .Int_Constraint
+	case UINT:
+		return .Uint_Constraint
 	case FLOAT:
 		return .Float_Constraint
 	case RANGE:
@@ -642,7 +646,7 @@ is_bool :: proc(value: Type) -> bool {
 }
 
 is_constraint :: proc(value: Type) -> bool {
-	return value == INT || value == FLOAT || value == RANGE
+	return value == INT || value == UINT || value == FLOAT || value == RANGE
 }
 
 // constraint_target reports the concrete type a constraint binding (local, or a
@@ -656,6 +660,8 @@ constraint_target :: proc(constraint, inferred: Type, store: ^Store = nil) -> Ty
 	switch constraint {
 	case INT:
 		return inferred if is_concrete_integer(inferred) else INVALID
+	case UINT:
+		return inferred if is_unsigned(inferred) else INVALID
 	case FLOAT:
 		if is_float(inferred) {
 			return inferred
@@ -673,6 +679,8 @@ constraint_accepts :: proc(constraint, concrete: Type, store: ^Store = nil) -> b
 	switch constraint {
 	case INT:
 		return is_concrete_integer(concrete)
+	case UINT:
+		return is_unsigned(concrete)
 	case FLOAT:
 		return is_float(concrete)
 	case RANGE:
@@ -1686,6 +1694,19 @@ smallest_signed_for_literal :: proc(value: i64) -> Type {
 	return I64
 }
 
+smallest_unsigned_for_literal :: proc(value: u64) -> Type {
+	if value <= 255 {
+		return U8
+	}
+	if value <= 65535 {
+		return U16
+	}
+	if value <= 4294967295 {
+		return U32
+	}
+	return U64
+}
+
 name :: proc(value: Type) -> string {
 	switch value {
 	case INVALID:       return "<invalid>"
@@ -1693,6 +1714,7 @@ name :: proc(value: Type) -> string {
 	case ANYOPAQUE:     return "anyopaque"
 	case BOOL:          return "bool"
 	case INT:           return "int"
+	case UINT:          return "uint"
 	case FLOAT:         return "float"
 	case RANGE:         return "range"
 	case I8:            return "i8"

compiler_tests.odin

@@ -1485,6 +1485,7 @@ main func() void {
 	_ = maxval!(u8, u16)
 	_ = minval!(1)
 	_ = maxval!(int)
+	_ = maxval!(uint)
 	_ = maxval!(f32)
 	_ = maxval!(bool)
 	_ = maxval!(Named)
@@ -1513,7 +1514,7 @@ main func() void {
 	}
 	testing.expect_value(t, bad_arity, 2)
 	testing.expect(t, bad_type)
-	testing.expect_value(t, bad_target, 5)
+	testing.expect_value(t, bad_target, 6)
 }
 
 @(test)
@@ -12778,3 +12779,287 @@ main func() void {
 	testing.expect(t, types.is_slice(nested_field, &hir_module.types))
 	testing.expect_value(t, types.child_type(nested_field, &hir_module.types), types.INT)
 }
+
+@(test)
+parser_records_native_tests_and_test_imports :: proc(t: ^testing.T) {
+	text := `test import "../math"
+
+addition test {
+	return
+}
+`
+	source_file := source.Source{path="tests.bro", text=text}
+	diagnostics := source.init_diagnostics(&source_file)
+	defer source.destroy_diagnostics(&diagnostics)
+	symbols := symbol.init_table()
+	defer symbol.destroy_table(&symbols)
+	stream := lexer.lex(&source_file, &diagnostics, &symbols)
+	defer delete(stream.items)
+	module := parser.parse(&stream, &source_file, &diagnostics)
+	defer ast.destroy_module(&module)
+
+	testing.expect_value(t, len(diagnostics.items), 0)
+	testing.expect_value(t, len(module.imports), 1)
+	testing.expect(t, module.imports[0].test_only)
+	testing.expect_value(t, module.imports[0].alias, symbol.INVALID)
+	testing.expect_value(t, len(module.functions), 1)
+	testing.expect(t, module.functions[0].test)
+	testing.expect_value(t, symbol.resolve(&symbols, module.functions[0].name), "addition")
+}
+
+@(test)
+native_test_framework_discovers_reports_and_preserves_main :: proc(t: ^testing.T) {
+	directory := "/tmp/brolang-test-native-framework"
+	root := "/tmp/brolang-test-native-framework/root"
+	dependency := "/tmp/brolang-test-native-framework/dependency"
+	root_path := "/tmp/brolang-test-native-framework/root/main.bro"
+	dependency_path := "/tmp/brolang-test-native-framework/dependency/math.bro"
+	test_output := "/tmp/brolang-test-native-framework-tests"
+	app_output := "/tmp/brolang-test-native-framework-app"
+	_ = os2.remove_all(directory)
+	defer _ = os2.remove_all(directory)
+	defer _ = os.remove(test_output)
+	defer _ = os.remove(app_output)
+	testing.expect(t, os2.make_directory_all(root) == nil)
+	testing.expect(t, os2.make_directory_all(dependency) == nil)
+
+	root_text := `testing :: import "@std/testing"
+
+test import "../dependency"
+
+main func() i32 { return 77 }
+
+root_passes test {
+	try testing.expect(true)
+}
+
+root_fails test {
+	try testing.expect_equal(42, 41)
+}
+
+root_continues test {
+	try testing.expect(true)
+}
+`
+	dependency_text := `testing :: import "@std/testing"
+
+dependency_passes test {
+	try testing.expect(true)
+}
+`
+	testing.expect(t, os.write_entire_file(root_path, transmute([]byte)root_text))
+	testing.expect(t, os.write_entire_file(dependency_path, transmute([]byte)dependency_text))
+
+	app_status := compiler_core.compile_package(
+		root, app_output, nil, target.DEFAULT, cimport.Options{}, ".",
+	)
+	testing.expect_value(t, app_status, 0)
+	app_state := run_executable(app_output)
+	testing.expect_value(t, app_state.exit_code, 77)
+
+	test_status := compiler_core.compile_package(
+		root, test_output, nil, target.DEFAULT, cimport.Options{}, ".", .Test,
+	)
+	testing.expect_value(t, test_status, 0)
+	state, stdout, stderr, _ := os2.process_exec(
+		os2.Process_Desc{command=[]string{test_output}},
+		context.allocator,
+	)
+	defer delete(stdout)
+	defer delete(stderr)
+	output := string(stderr)
+	testing.expect_value(t, state.exit_code, 1)
+	testing.expect(t, strings.contains(output, "PASS root.root_passes"))
+	testing.expect(t, strings.contains(output, "FAIL root.root_fails"))
+	testing.expect(t, strings.contains(output, "expected 42, found 41"))
+	testing.expect(t, strings.contains(output, "PASS root.root_continues"))
+	testing.expect(t, strings.contains(output, "PASS dependency.dependency_passes"))
+	testing.expect(t, strings.contains(output, root_path))
+	testing.expect(t, strings.contains(output, "3 passed, 1 failed"))
+}
+
+@(test)
+uint_constraint_parses_as_type_and_comptime_value :: proc(t: ^testing.T) {
+	text := `value uint :: 1
+Constraint :: uint
+`
+	source_file := source.Source{path="uint.bro", text=text}
+	diagnostics := source.init_diagnostics(&source_file)
+	defer source.destroy_diagnostics(&diagnostics)
+	symbols := symbol.init_table()
+	defer symbol.destroy_table(&symbols)
+	stream := lexer.lex(&source_file, &diagnostics, &symbols)
+	defer delete(stream.items)
+	module := parser.parse(&stream, &source_file, &diagnostics)
+	defer ast.destroy_module(&module)
+
+	testing.expect_value(t, len(diagnostics.items), 0)
+	testing.expect_value(t, len(module.globals), 2)
+	testing.expect_value(t, module.globals[0].type, types.UINT)
+	testing.expect_value(t, module.exprs[module.globals[1].expr].kind, ast.Expr_Kind.Type)
+	testing.expect_value(t, module.exprs[module.globals[1].expr].type, types.UINT)
+}
+
+@(test)
+uint_constraint_uses_smallest_unsigned_types_and_widens :: proc(t: ^testing.T) {
+	text := `Zero uint :: 0
+Byte uint :: 255
+Word uint :: 256
+Dword uint :: 65536
+Maximum uint :: 18446744073709551615
+Counter uint = 1
+
+widen func() uint {
+	value uint = 1
+	value = 1000
+	return value
+}
+
+widen_global func() void { Counter = 1000 }
+
+main func() void {
+	_ = Zero
+	_ = Byte
+	_ = Word
+	_ = Dword
+	_ = Maximum
+	_ = widen()
+	widen_global()
+}
+`
+	source_file := source.Source{path="uint_types.bro", text=text}
+	diagnostics := source.init_diagnostics(&source_file)
+	defer source.destroy_diagnostics(&diagnostics)
+	symbols := symbol.init_table()
+	defer symbol.destroy_table(&symbols)
+	stream := lexer.lex(&source_file, &diagnostics, &symbols)
+	defer delete(stream.items)
+	ast_module := parser.parse(&stream, &source_file, &diagnostics)
+	defer ast.destroy_module(&ast_module)
+	hir_module := checker.check(&ast_module, &diagnostics, &symbols)
+	defer hir.destroy_module(&hir_module)
+
+	expected := []types.Type{types.U8, types.U8, types.U16, types.U32, types.U64, types.U16}
+	for value_type, index in expected {
+		testing.expect_value(t, hir_module.globals[index].type, value_type)
+	}
+	widen_symbol := symbol.intern(&symbols, "widen")
+	found_widen := false
+	for function in hir_module.functions {
+		if function.name != widen_symbol {
+			continue
+		}
+		found_widen = true
+		testing.expect_value(t, function.result, types.U16)
+		testing.expect_value(t, function.locals[0].type, types.U16)
+	}
+	testing.expect_value(t, len(diagnostics.items), 0)
+	testing.expect(t, found_widen)
+}
+
+@(test)
+uint_constraint_infers_boundaries_calls_and_records :: proc(t: ^testing.T) {
+	directory := "/tmp/brolang-test-uint-constraint"
+	main_path := "/tmp/brolang-test-uint-constraint/main.bro"
+	output := "/tmp/brolang-test-uint-constraint-output"
+	text := `Box :: struct { value uint }
+
+identity func(value uint) uint { return value }
+whole func(value int) int { return value }
+max_value func() uint { return 18446744073709551615 }
+
+make_box func(value usize) Box { return Box{value = value} }
+
+main func() i32 {
+	zero uint :: 0
+	byte uint :: 255
+	word uint :: 256
+	word_max uint :: 65535
+	dword uint :: 65536
+	maximum uint :: 18446744073709551615
+	platform usize = 7
+	c_value c_uint = c_uint(9)
+	box Box = make_box(7)
+	signed isize = -1
+	if (identity(zero) != 0) return 1
+	if (identity(byte) != 255) return 2
+	if (identity(word) != 256) return 3
+	if (identity(word_max) != 65535) return 4
+	if (identity(dword) != 65536) return 5
+	if (identity(maximum) != 18446744073709551615) return 6
+	if (box.value != 7) return 7
+	if (signed != -1) return 8
+	if (identity(platform) != 7) return 9
+	if (identity(c_value) != c_value) return 10
+	if (whole(word) != 256) return 11
+	if (max_value() != 18446744073709551615) return 12
+	return 0
+}
+`
+	_ = os2.remove_all(directory)
+	defer _ = os2.remove_all(directory)
+	defer _ = os.remove(output)
+	testing.expect(t, os.make_directory(directory) == nil)
+	testing.expect(t, os.write_entire_file(main_path, transmute([]byte)text))
+	testing.expect_value(t, compiler_core.compile_package(directory, output), 0)
+	state := run_executable(output)
+	testing.expect_value(t, state.exit_code, 0)
+}
+
+@(test)
+uint_constraint_rejects_other_families_and_recovers_records_as_u64 :: proc(t: ^testing.T) {
+	text := `Unresolved :: struct { value uint }
+Conflict :: struct { value uint }
+
+take func(value uint) uint { return value }
+bad_result func() uint { return -1 }
+
+bad func(signed i32, decimal f64) void {
+	_ = take(signed)
+	_ = take(decimal)
+	negative uint :: -1
+	a Conflict = Conflict{value = signed}
+	_ = negative
+	_ = a
+}
+
+Overflow uint :: 18446744073709551616
+NegativeGlobal uint :: -1
+main func() void {
+	bad(1, 1.0)
+	_ = bad_result()
+}
+`
+	source_file := source.Source{path="bad_uint.bro", text=text}
+	diagnostics := source.init_diagnostics(&source_file)
+	defer source.destroy_diagnostics(&diagnostics)
+	symbols := symbol.init_table()
+	defer symbol.destroy_table(&symbols)
+	stream := lexer.lex(&source_file, &diagnostics, &symbols)
+	defer delete(stream.items)
+	ast_module := parser.parse(&stream, &source_file, &diagnostics)
+	defer ast.destroy_module(&ast_module)
+	hir_module := checker.check(&ast_module, &diagnostics, &symbols)
+	defer hir.destroy_module(&hir_module)
+
+	signed_error := false
+	float_error := false
+	negative_error := false
+	field_error := false
+	overflow_error := false
+	global_error := false
+	result_error := false
+	for diagnostic in diagnostics.items {
+		signed_error = signed_error || strings.contains(diagnostic.message, "cannot pass i32 to 'uint' parameter 'value'")
+		float_error = float_error || strings.contains(diagnostic.message, "cannot pass f64 to 'uint' parameter 'value'")
+		negative_error = negative_error || strings.contains(diagnostic.message, "could not resolve the 'uint' constraint for local 'negative'")
+		field_error = field_error || strings.contains(diagnostic.message, "type i32 does not satisfy the 'uint' constraint for field 'Conflict.value'")
+		overflow_error = overflow_error || strings.contains(diagnostic.message, "magnitude does not fit in u64")
+		global_error = global_error || strings.contains(diagnostic.message, "could not resolve the 'uint' constraint for global 'NegativeGlobal'")
+		result_error = result_error || strings.contains(diagnostic.message, "could not resolve a concrete result type for 'bad_result'")
+	}
+	unresolved, unresolved_ok := named_record_field_type(&hir_module, &symbols, "Unresolved", "value")
+	testing.expect(t, signed_error && float_error && negative_error && field_error && overflow_error && global_error && result_error)
+	testing.expect(t, unresolved_ok)
+	testing.expect_value(t, unresolved, types.U64)
+}

extension.toml

@@ -9,5 +9,5 @@ languages = ["languages/brolang"]
 
 [grammars.brolang]
 repository = "file:///Users/valdemar/Developer/Personal/Languages/brolang"
-rev = "03f5445509575fb72226e8b4bbf230d7905b7b8e"
+rev = "71357b2866d2a558f80b6d5cc65761fb853e74d3"
 path = "tree-sitter-brolang"

languages/brolang/highlights.scm

@@ -35,6 +35,7 @@
 
 (type_declaration name: (identifier) @type)
 (function_declaration name: (identifier) @function)
+(test_declaration name: (identifier) @function)
 (parameter name: (identifier) @variable.parameter)
 
 (intrinsic_call_expression function: (identifier) @function.builtin)
@@ -53,6 +54,7 @@
 
 [
   "func"
+	"test"
   "c_func"
   "struct"
   "c_struct"

main.odin

@@ -103,6 +103,9 @@ print_usage :: proc() {
 	fmt.eprintln(
 		"       brolang build [root]   (reads root/build.bro; writes root/build/name)",
 	)
+	fmt.eprintln(
+		"       brolang test [root]    (reads root/build.bro; writes and runs root/build/name-test)",
+	)
 	fmt.eprintln(
 		"       brolang new <project-path>",
 	)
@@ -122,6 +125,10 @@ is_build_command :: proc(arg: string) -> bool {
 	return arg == "build"
 }
 
+is_test_command :: proc(arg: string) -> bool {
+	return arg == "test"
+}
+
 is_new_command :: proc(arg: string) -> bool {
 	return arg == "new"
 }
@@ -609,6 +616,14 @@ main :: proc() {
 		root := os2.args[2] if len(os2.args) == 3 else ""
 		os2.exit(compiler.run_build(root))
 	}
+	if len(os2.args) >= 2 && is_test_command(os2.args[1]) {
+		if len(os2.args) > 3 {
+			print_usage()
+			os2.exit(2)
+		}
+		root := os2.args[2] if len(os2.args) == 3 else ""
+		os2.exit(compiler.run_tests(root))
+	}
 	if len(os2.args) >= 2 && is_new_command(os2.args[1]) {
 		if len(os2.args) != 3 {
 			print_usage()

std/testing/testing.bro

@@ -0,0 +1,39 @@
+debug :: import "@std/debug"
+
+Error :: enum {
+	expectation_failed
+}
+
+SourceLocation :: struct {
+	file   []u8
+	line   usize
+	column usize
+}
+
+expect func(condition bool, location SourceLocation) void ! Error {
+	if (!condition) {
+		debug.print("{s}:{d}:{d}: expectation failed\n", {location.file, location.line, location.column})
+		return .expectation_failed
+	}
+}
+
+expect_equal func($T type, expected, actual T, location SourceLocation) void ! Error {
+	if (expected != actual) {
+		debug.print("{s}:{d}:{d}: expected {}, found {}\n", {location.file, location.line, location.column, expected, actual})
+		return .expectation_failed
+	}
+}
+
+run func(name []u8, callback *func() void ! Error) bool {
+	debug.print("RUN  {s}\n", {name,})
+	callback() catch |_| {
+		debug.print("FAIL {s}\n", {name,})
+		return false
+	}
+	debug.print("PASS {s}\n", {name,})
+	return true
+}
+
+summary func(passed, failed i32) void {
+	debug.print("{d} passed, {d} failed\n", {passed, failed})
+}

tree-sitter-brolang/grammar.js

@@ -40,7 +40,9 @@ module.exports = grammar({
 
     _top_level_declaration: $ => choice(
       $.import_declaration,
+      $.test_import_declaration,
       $.function_declaration,
+      $.test_declaration,
       $.type_declaration,
       $.global_constant_declaration,
       $.global_variable_declaration,
@@ -53,6 +55,20 @@ module.exports = grammar({
       field('path', $.string),
     ),
 
+    test_import_declaration: $ => seq(
+      'test',
+      'import',
+      repeat($._newline),
+      field('path', $.string),
+    ),
+
+    test_declaration: $ => seq(
+      field('name', $.identifier),
+      'test',
+      repeat($._newline),
+      field('body', $.block),
+    ),
+
     function_declaration: $ => seq(
       optional('hide'),
       field('name', $.identifier),
@@ -212,7 +228,7 @@ module.exports = grammar({
     _type_constant: $ => seq(optional('-'), choice($.integer, $.character)),
 
     builtin_type: _ => choice(
-      'void', 'anyopaque', 'bool', 'int', 'float', 'range',
+      'void', 'anyopaque', 'bool', 'int', 'uint', 'float', 'range',
       'i8', 'i16', 'i32', 'i64', 'u8', 'u16', 'u32', 'u64',
       'isize', 'usize', 'f32', 'f64',
       'c_char', 'c_schar', 'c_uchar', 'c_short', 'c_ushort',

tree-sitter-brolang/queries/highlights.scm

@@ -35,6 +35,7 @@
 
 (type_declaration name: (identifier) @type)
 (function_declaration name: (identifier) @function)
+(test_declaration name: (identifier) @function)
 (parameter name: (identifier) @variable.parameter)
 
 (intrinsic_call_expression function: (identifier) @function.builtin)
@@ -53,6 +54,7 @@
 
 [
   "func"
+	"test"
   "c_func"
   "struct"
   "c_struct"

tree-sitter-brolang/src/grammar.json

@@ -26,10 +26,18 @@
           "type": "SYMBOL",
           "name": "import_declaration"
         },
+        {
+          "type": "SYMBOL",
+          "name": "test_import_declaration"
+        },
         {
           "type": "SYMBOL",
           "name": "function_declaration"
         },
+        {
+          "type": "SYMBOL",
+          "name": "test_declaration"
+        },
         {
           "type": "SYMBOL",
           "name": "type_declaration"
@@ -100,6 +108,66 @@
         }
       ]
     },
+    "test_import_declaration": {
+      "type": "SEQ",
+      "members": [
+        {
+          "type": "STRING",
+          "value": "test"
+        },
+        {
+          "type": "STRING",
+          "value": "import"
+        },
+        {
+          "type": "REPEAT",
+          "content": {
+            "type": "SYMBOL",
+            "name": "_newline"
+          }
+        },
+        {
+          "type": "FIELD",
+          "name": "path",
+          "content": {
+            "type": "SYMBOL",
+            "name": "string"
+          }
+        }
+      ]
+    },
+    "test_declaration": {
+      "type": "SEQ",
+      "members": [
+        {
+          "type": "FIELD",
+          "name": "name",
+          "content": {
+            "type": "SYMBOL",
+            "name": "identifier"
+          }
+        },
+        {
+          "type": "STRING",
+          "value": "test"
+        },
+        {
+          "type": "REPEAT",
+          "content": {
+            "type": "SYMBOL",
+            "name": "_newline"
+          }
+        },
+        {
+          "type": "FIELD",
+          "name": "body",
+          "content": {
+            "type": "SYMBOL",
+            "name": "block"
+          }
+        }
+      ]
+    },
     "function_declaration": {
       "type": "SEQ",
       "members": [
@@ -1408,6 +1476,10 @@
           "type": "STRING",
           "value": "int"
         },
+        {
+          "type": "STRING",
+          "value": "uint"
+        },
         {
           "type": "STRING",
           "value": "float"

tree-sitter-brolang/src/node-types.json

@@ -1852,6 +1852,14 @@
           "type": "import_declaration",
           "named": true
         },
+        {
+          "type": "test_declaration",
+          "named": true
+        },
+        {
+          "type": "test_import_declaration",
+          "named": true
+        },
         {
           "type": "type_declaration",
           "named": true
@@ -2000,6 +2008,48 @@
       ]
     }
   },
+  {
+    "type": "test_declaration",
+    "named": true,
+    "fields": {
+      "body": {
+        "multiple": false,
+        "required": true,
+        "types": [
+          {
+            "type": "block",
+            "named": true
+          }
+        ]
+      },
+      "name": {
+        "multiple": false,
+        "required": true,
+        "types": [
+          {
+            "type": "identifier",
+            "named": true
+          }
+        ]
+      }
+    }
+  },
+  {
+    "type": "test_import_declaration",
+    "named": true,
+    "fields": {
+      "path": {
+        "multiple": false,
+        "required": true,
+        "types": [
+          {
+            "type": "string",
+            "named": true
+          }
+        ]
+      }
+    }
+  },
   {
     "type": "tuple_literal",
     "named": true,
@@ -2737,6 +2787,10 @@
     "type": "struct",
     "named": false
   },
+  {
+    "type": "test",
+    "named": false
+  },
   {
     "type": "true",
     "named": false
@@ -2761,6 +2815,10 @@
     "type": "u8",
     "named": false
   },
+  {
+    "type": "uint",
+    "named": false
+  },
   {
     "type": "undefined",
     "named": true

tree-sitter-brolang/test/corpus/syntax.txt

@@ -364,7 +364,30 @@ main func() void {
                 (expression
                   (sink))
                 (expression
-                  (identifier))))))))))
+              (identifier))))))))))
+
+==================
+Native tests
+==================
+
+math :: import "../math"
+test import "../math"
+
+addition test {}
+
+---
+
+(source_file
+  (import_declaration
+    (identifier)
+    (string
+      (string_content)))
+  (test_import_declaration
+    (string
+      (string_content)))
+  (test_declaration
+    (identifier)
+    (block)))
 
 ==================
 Expanded match arms
@@ -373,7 +396,7 @@ Expanded match arms
 Kind :: enum { one, two }
 Value :: union(enum) { number i32, empty void }
 
-test func(kind Kind, value Value) void {
+visit func(kind Kind, value Value) void {
 	match kind {
 		.one: {}
 		expand |tag|: _ = tag
@@ -470,3 +493,19 @@ test func(kind Kind, value Value) void {
                       (sink))
                     (expression
                       (identifier))))))))))))
+
+==================
+Unsigned constraint
+==================
+
+value uint :: 255
+
+---
+
+(source_file
+  (global_constant_declaration
+    (identifier)
+    (type
+      (builtin_type))
+    (expression
+      (integer))))

tree-sitter-brolang/test/highlight/intrinsics.bro

@@ -1,6 +1,9 @@
 hide helper func() void {}
 # <- keyword
 
+value uint :: 1
+#     ^^^^ type.builtin
+
 main func() void {
 	_ = sizeof!(i32)
 #	    ^^^^^^ function.builtin