broaden type inference from context (arithmetic expressions)

2026-06-26 16:10:23 +02:00
parent ff69e1da83
commit cfc1b2cb42
3 changed files with 340 additions and 87 deletions
@@ -6629,3 +6629,120 @@ contextual_inference_rejects_local_constant_that_does_not_fit :: proc(t: ^testin
 	}
 	testing.expect(t, found)
 }
+
+@(test)
+contextual_inference_flows_through_numeric_arithmetic :: proc(t: ^testing.T) {
+	text := `take_u16 :: func(v u16) void {}
+take_f32 :: func(v f32) void {}
+G :: 10
+H u16 :: G + 2
+GF :: 1.5
+HF f32 :: GF + 2.5
+CG :: 5
+CFG :: 1.0
+get :: func() f32 {
+	seed f32 :: 2.0
+	c :: seed + 3.0
+	d :: 4.0 + seed
+	return c + d
+}
+main :: func() void {
+	a :: 10
+	b u16 :: a + 2
+	x :: 1.5
+	y f32 :: x + 2.5
+	z f32 :: 2.5 + x
+	call_i :: 7
+	call_f :: 1.25
+	take_u16(call_i + 3)
+	take_f32(call_f + 3.0)
+	take_u16(CG + 1)
+	take_f32(CFG + 1.0)
+	_ = b
+	_ = y
+	_ = z
+	_ = H
+	_ = HF
+	_ = get()
+}
+`
+	source_file := source.Source{path="test.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)
+
+	testing.expect_value(t, len(diagnostics.items), 0)
+
+	global_ok := 0
+	for global in hir_module.globals {
+		name := symbol.resolve(&symbols, global.name)
+		switch name {
+		case "G", "H", "CG":
+			global_ok += 1 if types.equal(global.type, types.U16) else 0
+		case "GF", "HF", "CFG":
+			global_ok += 1 if types.equal(global.type, types.F32) else 0
+		}
+	}
+	testing.expect_value(t, global_ok, 6)
+
+	main_ok := 0
+	get_ok := false
+	for function in hir_module.functions {
+		name := symbol.resolve(&symbols, function.name)
+		if name == "get" {
+			get_ok = types.equal(function.result, types.F32)
+			for local in function.locals {
+				local_name := symbol.resolve(&symbols, local.name)
+				if local_name == "c" || local_name == "d" {
+					main_ok += 1 if types.equal(local.type, types.F32) else 0
+				}
+			}
+		} else if name == "main" {
+			for local in function.locals {
+				local_name := symbol.resolve(&symbols, local.name)
+				switch local_name {
+				case "a", "call_i":
+					main_ok += 1 if types.equal(local.type, types.U16) else 0
+				case "x", "call_f":
+					main_ok += 1 if types.equal(local.type, types.F32) else 0
+				}
+			}
+		}
+	}
+	testing.expect(t, get_ok)
+	testing.expect_value(t, main_ok, 6)
+}
+
+@(test)
+contextual_inference_rejects_non_fitting_arithmetic_demand :: proc(t: ^testing.T) {
+	text := `BIG :: 100000
+C u8 :: BIG + 1
+main :: func() void {
+	_ = C
+}
+`
+	source_file := source.Source{path="test.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)
+
+	found := false
+	for diagnostic in diagnostics.items {
+		found = found || strings.contains(diagnostic.message, "cannot implicitly convert i32 to u8")
+	}
+	testing.expect(t, found)
+}