Fix string aliases in deriveCompare (#86)

awalterschulze · Jun 20, 2024 · f4ac349 · f4ac349
1 parent e3f2fdf
commit f4ac349
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Showing 4 changed files with 90 additions and 14 deletions.
diff --git a/plugin/compare/compare.go b/plugin/compare/compare.go
@@ -251,7 +251,11 @@ func (g *gen) genStatement(typ types.Type, this, that string) error {
 	case *types.Basic:
 		switch ttyp.Kind() {
 		case types.String:
-			p.P("return %s.Compare(%s, %s)", g.stringsPkg(), this, that)
+			if types.Identical(typ, ttyp) {
+				p.P("return %s.Compare(%s, %s)", g.stringsPkg(), this, that)
+			} else {
+				p.P("return %s.Compare(string(%s), string(%s))", g.stringsPkg(), this, that)
+			}
 		case types.Complex128, types.Complex64:
 			p.P("if thisr, thatr := real(%s), real(%s); thisr == thatr {", this, that)
 			p.In()
@@ -473,7 +477,11 @@ func (g *gen) field(thisField, thatField string, fieldType types.Type) (string,
 	switch typ := fieldType.Underlying().(type) {
 	case *types.Basic:
 		if typ.Kind() == types.String {
-			return fmt.Sprintf("%s.Compare(%s, %s)", g.stringsPkg(), thisField, thatField), nil
+			if types.Identical(fieldType, typ) {
+				return fmt.Sprintf("%s.Compare(%s, %s)", g.stringsPkg(), thisField, thatField), nil
+			} else {
+				return fmt.Sprintf("%s.Compare(string(%s), string(%s))", g.stringsPkg(), thisField, thatField), nil
+			}
 		}
 		return fmt.Sprintf("%s(%s, %s)", g.GetFuncName(fieldType, fieldType), thisField, thatField), nil
 	case *types.Pointer:

diff --git a/test/normal/compare_test.go b/test/normal/compare_test.go
@@ -128,3 +128,31 @@ func TestCompareCurry(t *testing.T) {
 		t.Fatalf("compare: got %d want %d", c, 1)
 	}
 }
+
+func TestCompareStringAlias(t *testing.T) {
+	this := stringAlias("aaa")
+	that := stringAlias("bbb")
+	if c := deriveCompareStringAlias(this, this); c != 0 {
+		t.Fatalf("compare: got %d want %d", c, 0)
+	}
+	if c := deriveCompareStringAlias(this, that); c != -1 {
+		t.Fatalf("compare: got %d want %d", c, 0)
+	}
+	if c := deriveCompareStringAlias(that, this); c != 1 {
+		t.Fatalf("compare: got %d want %d", c, 0)
+	}
+}
+
+func TestCompareStringAliasField(t *testing.T) {
+	this := StructWithStringAlias{stringAlias("aaa")}
+	that := StructWithStringAlias{stringAlias("bbb")}
+	if c := deriveCompareStructWithStringAlias(this, this); c != 0 {
+		t.Fatalf("compare: got %d want %d", c, 0)
+	}
+	if c := deriveCompareStructWithStringAlias(this, that); c != -1 {
+		t.Fatalf("compare: got %d want %d", c, 0)
+	}
+	if c := deriveCompareStructWithStringAlias(that, this); c != 1 {
+		t.Fatalf("compare: got %d want %d", c, 0)
+	}
+}
diff --git a/test/normal/derived.gen.go b/test/normal/derived.gen.go
diff --git a/test/normal/types.go b/test/normal/types.go
@@ -20,6 +20,10 @@ func true5(lt *LocalType) (*LocalType, bool) {
 	return lt, true
 }
 
+type StructWithStringAlias struct {
+	Field stringAlias
+}
+
 type DeriveTheDerived struct {
 	Field int
 }