fix: directive error positions and messages (#1756)

Fixes #1635

I also noticed that the directive errors were being shown on the `func`
instead of the location of the directive so added `GetPosition` to
directives as well.

![Screenshot 2024-06-12 at 3 52
24 PM](https://github.com/TBD54566975/ftl/assets/51647/d5aaa6d2-2bba-4727-85b2-fd3965bb9ada)

and

![Screenshot 2024-06-12 at 3 53
31 PM](https://github.com/TBD54566975/ftl/assets/51647/a5d60dcb-c67b-4799-8445-529f36cfe724)

go-runtime/compile/parser.go

@@ -29,6 +29,7 @@ type directiveWrapper struct {
 type directive interface {
 	directive()
 	SetPosition(pos schema.Position)
+	GetPosition() schema.Position
 }
 
 type exportable interface {
@@ -48,6 +49,10 @@ func (d *directiveVerb) SetPosition(pos schema.Position) {
 	d.Pos = pos
 }
 
+func (d *directiveVerb) GetPosition() schema.Position {
+	return d.Pos
+}
+
 func (d *directiveVerb) String() string {
 	if d.Export {
 		return "ftl:verb export"
@@ -71,6 +76,10 @@ func (d *directiveData) SetPosition(pos schema.Position) {
 	d.Pos = pos
 }
 
+func (d *directiveData) GetPosition() schema.Position {
+	return d.Pos
+}
+
 func (d *directiveData) String() string {
 	if d.Export {
 		return "ftl:data export"
@@ -94,6 +103,10 @@ func (d *directiveEnum) SetPosition(pos schema.Position) {
 	d.Pos = pos
 }
 
+func (d *directiveEnum) GetPosition() schema.Position {
+	return d.Pos
+}
+
 func (d *directiveEnum) String() string {
 	if d.Export {
 		return "ftl:enum export"
@@ -117,6 +130,10 @@ func (d *directiveTypeAlias) SetPosition(pos schema.Position) {
 	d.Pos = pos
 }
 
+func (d *directiveTypeAlias) GetPosition() schema.Position {
+	return d.Pos
+}
+
 func (d *directiveTypeAlias) String() string {
 	if d.Export {
 		return "ftl:typealias export"
@@ -141,6 +158,10 @@ func (d *directiveIngress) SetPosition(pos schema.Position) {
 	d.Pos = pos
 }
 
+func (d *directiveIngress) GetPosition() schema.Position {
+	return d.Pos
+}
+
 func (d *directiveIngress) String() string {
 	w := &strings.Builder{}
 	fmt.Fprintf(w, "ftl:ingress %s", d.Method)
@@ -162,8 +183,12 @@ func (d *directiveCronJob) SetPosition(pos schema.Position) {
 	d.Pos = pos
 }
 
+func (d *directiveCronJob) GetPosition() schema.Position {
+	return d.Pos
+}
+
 func (d *directiveCronJob) String() string {
-	return fmt.Sprintf("cron %s", d.Cron)
+	return fmt.Sprintf("ftl:cron %s", d.Cron)
 }
 
 type directiveRetry struct {
@@ -180,6 +205,10 @@ func (d *directiveRetry) SetPosition(pos schema.Position) {
 	d.Pos = pos
 }
 
+func (d *directiveRetry) GetPosition() schema.Position {
+	return d.Pos
+}
+
 func (d *directiveRetry) String() string {
 	components := []string{"retry"}
 	if d.Count != nil {
@@ -205,6 +234,10 @@ func (d *directiveSubscriber) SetPosition(pos schema.Position) {
 	d.Pos = pos
 }
 
+func (d *directiveSubscriber) GetPosition() schema.Position {
+	return d.Pos
+}
+
 func (d *directiveSubscriber) String() string {
 	return fmt.Sprintf("subscribe %s", d.Name)
 }
@@ -222,8 +255,12 @@ func (d *directiveExport) SetPosition(pos schema.Position) {
 	d.Pos = pos
 }
 
+func (d *directiveExport) GetPosition() schema.Position {
+	return d.Pos
+}
+
 func (d *directiveExport) String() string {
-	return "export"
+	return "ftl:export"
 }
 
 var directiveParser = participle.MustBuild[directiveWrapper](

go-runtime/compile/schema.go

@@ -60,6 +60,10 @@ func noEndColumnErrorf(pos token.Pos, format string, args ...interface{}) *schem
 	return tokenErrorf(pos, "", format, args...)
 }
 
+func unexpectedDirectiveErrorf(dir directive, format string, args ...interface{}) *schema.Error {
+	return schema.Errorf(dir.GetPosition(), 0, format, args...)
+}
+
 func tokenErrorf(pos token.Pos, tokenText string, format string, args ...interface{}) *schema.Error {
 	goPos := goPosToSchemaPos(pos)
 	endColumn := goPos.Column
@@ -95,12 +99,6 @@ func (e errorSet) add(err *schema.Error) {
 	e[err.Error()] = err
 }
 
-func (e errorSet) addAll(errs ...*schema.Error) {
-	for _, err := range errs {
-		e.add(err)
-	}
-}
-
 func legacyExtractModuleSchema(dir string, sch *schema.Schema, out *analyzers.ExtractResult) error {
 	pkgs, err := packages.Load(&packages.Config{
 		Dir:  dir,
@@ -313,7 +311,7 @@ func extractTopicDecl(pctx *parseContext, node *ast.CallExpr, stack []ast.Node)
 		if _, ok := dir.(*directiveExport); ok {
 			export = true
 		} else {
-			pctx.errors.add(errorf(node, "unexpected directive attached for topic: %T", dir))
+			pctx.errors.add(unexpectedDirectiveErrorf(dir, "unexpected directive %q attached for topic", dir))
 		}
 	}
 
@@ -539,7 +537,7 @@ func parseFSMDecl(pctx *parseContext, node *ast.CallExpr, stack []ast.Node) {
 				MaxBackoff: retryDir.MaxBackoff,
 			})
 		} else {
-			pctx.errors.add(errorf(node, "unexpected directive attached for FSM: %T", dir))
+			pctx.errors.add(unexpectedDirectiveErrorf(dir, "unexpected directive %q attached for FSM", dir))
 		}
 	}
 }
@@ -1216,8 +1214,10 @@ func visitFuncDecl(pctx *parseContext, node *ast.FuncDecl) (verb *schema.Verb) {
 				Pos:  dir.Pos,
 				Name: dir.Name,
 			})
-		case *directiveData, *directiveEnum, *directiveTypeAlias, *directiveExport:
-			pctx.errors.add(errorf(node, "unexpected directive %T", dir))
+		case *directiveExport:
+			pctx.errors.add(unexpectedDirectiveErrorf(dir, "unexpected directive %q attached for verb, did you mean to use '//ftl:verb export' instead", dir))
+		case *directiveData, *directiveEnum, *directiveTypeAlias:
+			pctx.errors.add(unexpectedDirectiveErrorf(dir, "unexpected directive %q attached for verb", dir))
 		}
 	}
 	if !isVerb {

go-runtime/compile/schema_test.go

@@ -510,7 +510,7 @@ func TestErrorReporting(t *testing.T) {
 		`21:14-44: duplicate database declaration at 20:14-44`,
 		`24:2-10: unsupported type "error" for field "BadParam"`,
 		`27:2-17: unsupported type "uint64" for field "AnotherBadParam"`,
-		`31:1-2: unexpected directive *compile.directiveExport`,
+		`30:3-0: unexpected directive "ftl:export" attached for verb, did you mean to use '//ftl:verb export' instead`,
 		`36:36-39: unsupported request type "ftl/failing.Request"`,
 		`36:50-50: unsupported response type "ftl/failing.Response"`,
 		`37:16-29: call first argument must be a function but is an unresolved reference to lib.OtherFunc`,