Organize imports within ambient module declarations

src/harness/unittests/organizeImports.ts

@@ -325,6 +325,43 @@ F2();
 /*A*/import /*B*/ { /*C*/ F1 /*D*/, /*E*/ F2 /*F*/ } /*G*/ from /*H*/ "lib" /*I*/;/*J*/ //K
 
 F1();
+`,
+                },
+                libFile);
+
+            testOrganizeImports("AmbientModule",
+                {
+                    path: "/test.ts",
+                    content: `
+declare module "mod" {
+    import { F1 } from "lib";
+    import * as NS from "lib";
+    import { F2 } from "lib";
+
+    function F(f1: {} = F1, f2: {} = F2) {}
+}
+`,
+                },
+                libFile);
+
+            testOrganizeImports("TopLevelAndAmbientModule",
+                {
+                    path: "/test.ts",
+                    content: `
+import D from "lib";
+
+declare module "mod" {
+    import { F1 } from "lib";
+    import * as NS from "lib";
+    import { F2 } from "lib";
+
+    function F(f1: {} = F1, f2: {} = F2) {}
+}
+
+import E from "lib";
+import "lib";
+
+D();
 `,
                 },
                 libFile);

src/services/organizeImports.ts

@@ -13,13 +13,18 @@ namespace ts.OrganizeImports {
         host: LanguageServiceHost,
         program: Program) {
 
-        // TODO (https://github.com/Microsoft/TypeScript/issues/10020): sort *within* ambient modules (find using isAmbientModule)
+        const changeTracker = textChanges.ChangeTracker.fromContext({ host, formatContext });
 
         // All of the old ImportDeclarations in the file, in syntactic order.
         const topLevelImportDecls = sourceFile.statements.filter(isImportDeclaration);
-
-        const changeTracker = textChanges.ChangeTracker.fromContext({ host, formatContext });
         organizeImportsWorker(topLevelImportDecls);
+
+        for (const ambientModule of sourceFile.statements.filter(isAmbientModule)) {
+            const ambientModuleBody = getModuleBlock(ambientModule as ModuleDeclaration);
+            const ambientModuleImportDecls = ambientModuleBody.statements.filter(isImportDeclaration);
+            organizeImportsWorker(ambientModuleImportDecls);
+        }
+
         return changeTracker.getChanges();
 
         function organizeImportsWorker(oldImportDecls: ReadonlyArray<ImportDeclaration>) {
@@ -54,6 +59,11 @@ namespace ts.OrganizeImports {
         }
     }
 
+    function getModuleBlock(moduleDecl: ModuleDeclaration): ModuleBlock | undefined {
+        const body = moduleDecl.body;
+        return body && !isIdentifier(body) && (isModuleBlock(body) ? body : getModuleBlock(body));
+    }
+
     function removeUnusedImports(oldImports: ReadonlyArray<ImportDeclaration>, sourceFile: SourceFile, program: Program) {
         const typeChecker = program.getTypeChecker();
         const jsxNamespace = typeChecker.getJsxNamespace();

tests/baselines/reference/organizeImports/AmbientModule.ts

@@ -0,0 +1,17 @@
+// ==ORIGINAL==
+
+declare module "mod" {
+    import { F1 } from "lib";
+    import * as NS from "lib";
+    import { F2 } from "lib";
+
+    function F(f1: {} = F1, f2: {} = F2) {}
+}
+
+// ==ORGANIZED==
+
+declare module "mod" {
+    import { F1, F2 } from "lib";
+
+    function F(f1: {} = F1, f2: {} = F2) {}
+}

tests/baselines/reference/organizeImports/TopLevelAndAmbientModule.ts

@@ -0,0 +1,30 @@
+// ==ORIGINAL==
+
+import D from "lib";
+
+declare module "mod" {
+    import { F1 } from "lib";
+    import * as NS from "lib";
+    import { F2 } from "lib";
+
+    function F(f1: {} = F1, f2: {} = F2) {}
+}
+
+import E from "lib";
+import "lib";
+
+D();
+
+// ==ORGANIZED==
+
+import "lib";
+import D from "lib";
+
+declare module "mod" {
+    import { F1, F2 } from "lib";
+
+    function F(f1: {} = F1, f2: {} = F2) {}
+}
+
+
+D();