fix(compiler): align contract route conflict validation

internal/compiler/routes.go

@@ -183,6 +183,9 @@ func validateRouteMethodConflicts(pages []gwdkir.Page, endpoints []gwdkir.GoEndp
 			if allowedPageOwnedQueryRouteConflict(previous, registration) {
 				continue
 			}
+			if identicalContractRouteRegistration(previous, registration) {
+				continue
+			}
 			diagnostics = append(diagnostics, ValidationError{
 				Code:   "route_method_conflict",
 				PageID: registration.PageID,
@@ -203,14 +206,15 @@ func validateRouteMethodConflicts(pages []gwdkir.Page, endpoints []gwdkir.GoEndp
 }
 
 type routeRegistration struct {
-	Kind    string
-	Owner   string
-	Method  string
-	Route   string
-	Pattern string
-	PageID  string
-	Source  string
-	Span    source.SourceSpan
+	Kind     string
+	Owner    string
+	Method   string
+	Route    string
+	Pattern  string
+	Contract string
+	PageID   string
+	Source   string
+	Span     source.SourceSpan
 }
 
 func routeRegistrations(pages []gwdkir.Page, endpoints []gwdkir.GoEndpoint, refs []gwdkir.ContractReference) []routeRegistration {
@@ -334,7 +338,8 @@ func routeRegistrations(pages []gwdkir.Page, endpoints []gwdkir.GoEndpoint, refs
 		if err := source.ValidateBackendRoutePath(ref.Path); err != nil {
 			continue
 		}
-		info, issues := parseRoute(ref.Path)
+		route := source.BackendRoutePath(ref.Path)
+		info, issues := parseRoute(route)
 		if len(issues) > 0 {
 			continue
 		}
@@ -344,14 +349,15 @@ func routeRegistrations(pages []gwdkir.Page, endpoints []gwdkir.GoEndpoint, refs
 		}
 		method := strings.ToUpper(strings.TrimSpace(ref.Method))
 		registrations = append(registrations, routeRegistration{
-			Kind:    "contract_" + kind,
-			Owner:   fmt.Sprintf("%s contract %s", kind, ref.Name),
-			Method:  method,
-			Route:   ref.Path,
-			Pattern: info.Pattern,
-			PageID:  ref.OwnerID,
-			Source:  ref.Source,
-			Span:    ref.Span,
+			Kind:     "contract_" + kind,
+			Owner:    fmt.Sprintf("%s contract %s", kind, ref.Name),
+			Method:   method,
+			Route:    route,
+			Pattern:  info.Pattern,
+			Contract: ref.Name,
+			PageID:   ref.OwnerID,
+			Source:   ref.Source,
+			Span:     ref.Span,
 		})
 	}
 	return registrations
@@ -361,6 +367,16 @@ func allowedPageOwnedQueryRouteConflict(first routeRegistration, current routeRe
 	return pageOwnedQueryRouteConflict(first, current) || pageOwnedQueryRouteConflict(current, first)
 }
 
+func identicalContractRouteRegistration(first routeRegistration, current routeRegistration) bool {
+	if !strings.HasPrefix(first.Kind, "contract_") || first.Kind != current.Kind {
+		return false
+	}
+	return first.Method == current.Method &&
+		first.Route == current.Route &&
+		first.Contract == current.Contract &&
+		first.PageID == current.PageID
+}
+
 func pageOwnedQueryRouteConflict(page routeRegistration, query routeRegistration) bool {
 	return page.Kind == "page" &&
 		query.Kind == "contract_query" &&

internal/compiler/validate_test.go

@@ -3572,6 +3572,16 @@ func TestValidateManifestRejectsInvalidContractReferenceRoutes(t *testing.T) {
 			viewBody: `<form method="post" action="/patients/{id}" g:command="patients.CreatePatient"></form>`,
 			message:  "without query, fragment, or params",
 		},
+		{
+			name:     "trailing slash command action",
+			viewBody: `<form method="post" action="/patients/" g:command="patients.CreatePatient"></form>`,
+			message:  "clean absolute path",
+		},
+		{
+			name:     "relative command action",
+			viewBody: `<form method="post" action="patients" g:command="patients.CreatePatient"></form>`,
+			message:  "local absolute path",
+		},
 		{
 			name:     "unsupported command method",
 			viewBody: `<form method="get" action="/patients" g:command="patients.CreatePatient"></form>`,
@@ -3835,6 +3845,26 @@ func TestValidateManifestRejectsRouteMethodConflicts(t *testing.T) {
 		}
 	})
 
+	t.Run("identical command route references are allowed", func(t *testing.T) {
+		app := appFixture{
+			Pages: []gwdkir.Page{{
+				ID:    "patients",
+				Route: "/patients",
+				Blocks: gwdkir.Blocks{
+					View: true,
+					ViewBody: `<main>
+  <form method="post" action="/patients" g:command="patients.CreatePatient"></form>
+  <form method="post" action="/patients" g:command="patients.CreatePatient"></form>
+</main>`,
+				},
+			}},
+		}
+
+		if err := validateManifest(gowdk.Config{}, app); err != nil {
+			t.Fatalf("expected identical command route references to be valid, got %v", err)
+		}
+	})
+
 	t.Run("query route conflicts with api", func(t *testing.T) {
 		app := appFixture{
 			Pages: []gwdkir.Page{{
@@ -3882,6 +3912,26 @@ func TestValidateManifestRejectsRouteMethodConflicts(t *testing.T) {
 			t.Fatalf("Missing duplicate query route_method_conflict diagnostic: %#v", diagnostics)
 		}
 	})
+
+	t.Run("identical query route references are allowed", func(t *testing.T) {
+		app := appFixture{
+			Pages: []gwdkir.Page{{
+				ID:    "patients",
+				Route: "/patients",
+				Blocks: gwdkir.Blocks{
+					View: true,
+					ViewBody: `<main>
+  <section g:query="patients.ListPatients"></section>
+  <section g:query="patients.ListPatients"></section>
+</main>`,
+				},
+			}},
+		}
+
+		if err := validateManifest(gowdk.Config{}, app); err != nil {
+			t.Fatalf("expected identical query route references to be valid, got %v", err)
+		}
+	})
 }
 
 func TestValidateManifestAllowsSameRouteWithDifferentMethods(t *testing.T) {

internal/source/source.go

@@ -67,6 +67,12 @@ func BackendRouteMethod(value string) string {
 	return strings.ToUpper(strings.TrimSpace(value))
 }
 
+// BackendRoutePath returns the normalized path key used by generated backend
+// routers after ValidateBackendRoutePath has accepted the source value.
+func BackendRoutePath(value string) string {
+	return path.Clean("/" + value)
+}
+
 // ValidateBackendRoutePath rejects paths that would be unsafe or ambiguous when
 // registered as generated backend routes.
 func ValidateBackendRoutePath(value string) error {
@@ -93,7 +99,7 @@ func ValidateBackendRoutePath(value string) error {
 			return fmt.Errorf("endpoint path %q must not contain control characters", value)
 		}
 	}
-	cleaned := path.Clean(value)
+	cleaned := BackendRoutePath(value)
 	if cleaned != value {
 		return fmt.Errorf("endpoint path %q must be a clean absolute path without dot segments, duplicate slashes, or trailing slash", value)
 	}

internal/source/source_test.go

@@ -43,3 +43,16 @@ func TestBackendRouteMethod(t *testing.T) {
 		t.Fatalf("expected normalized method POST, got %q", got)
 	}
 }
+
+func TestBackendRoutePath(t *testing.T) {
+	tests := map[string]string{
+		"/patients":  "/patients",
+		"/patients/": "/patients",
+		"patients":   "/patients",
+	}
+	for input, want := range tests {
+		if got := BackendRoutePath(input); got != want {
+			t.Fatalf("expected %q to normalize to %q, got %q", input, want, got)
+		}
+	}
+}