Introduce an organizeImports command

In phase 1, it coalesces imports from the same module and sorts the
results, but does not remove unused imports.

Some trivia is lost during coalescing, but none should be duplicated.

Author: amcasey

Jakefile.js

@@ -141,6 +141,7 @@ var harnessSources = harnessCoreSources.concat([
     "typingsInstaller.ts",
     "projectErrors.ts",
     "matchFiles.ts",
+    "organizeImports.ts",
     "initializeTSConfig.ts",
     "extractConstants.ts",
     "extractFunctions.ts",

src/harness/harnessLanguageService.ts

@@ -522,6 +522,9 @@ namespace Harness.LanguageService {
         getApplicableRefactors(): ts.ApplicableRefactorInfo[] {
             throw new Error("Not supported on the shim.");
         }
+        organizeImports(_scope: ts.OrganizeImportsScope, _formatOptions: ts.FormatCodeSettings): ReadonlyArray<ts.FileTextChanges> {
+            throw new Error("Not supported on the shim.");
+        }
         getEmitOutput(fileName: string): ts.EmitOutput {
             return unwrapJSONCallResult(this.shim.getEmitOutput(fileName));
         }

src/harness/tsconfig.json

@@ -117,6 +117,7 @@
         "./unittests/tsserverProjectSystem.ts",
         "./unittests/tscWatchMode.ts",
         "./unittests/matchFiles.ts",
+        "./unittests/organizeImports.ts",
         "./unittests/initializeTSConfig.ts",
         "./unittests/compileOnSave.ts",
         "./unittests/typingsInstaller.ts",

src/harness/unittests/organizeImports.ts

@@ -262,6 +262,8 @@ namespace ts.server {
                 CommandNames.GetApplicableRefactors,
                 CommandNames.GetEditsForRefactor,
                 CommandNames.GetEditsForRefactorFull,
+                CommandNames.OrganizeImports,
+                CommandNames.OrganizeImportsFull,
             ];
 
             it("should not throw when commands are executed with invalid arguments", () => {

src/harness/unittests/session.ts

@@ -629,6 +629,10 @@ namespace ts.server {
             };
         }
 
+        organizeImports(_scope: OrganizeImportsScope, _formatOptions: FormatCodeSettings): ReadonlyArray<FileTextChanges> {
+            return notImplemented();
+        }
+
         private convertCodeEditsToTextChanges(edits: protocol.FileCodeEdits[]): FileTextChanges[] {
             return edits.map(edit => {
                 const fileName = edit.fileName;

src/server/client.ts

@@ -113,6 +113,10 @@ namespace ts.server.protocol {
         /* @internal */
         GetEditsForRefactorFull = "getEditsForRefactor-full",
 
+        OrganizeImports = "organizeImports",
+        /* @internal */
+        OrganizeImportsFull = "organizeImports-full",
+
         // NOTE: If updating this, be sure to also update `allCommandNames` in `harness/unittests/session.ts`.
     }
 
@@ -547,6 +551,27 @@ namespace ts.server.protocol {
         renameFilename?: string;
     }
 
+    /**
+     * Organize imports by:
+     *   1) Removing unused imports
+     *   2) Coalescing imports from the same module
+     *   3) Sorting imports
+     */
+    export interface OrganizeImportsRequest extends Request {
+        command: CommandTypes.OrganizeImports;
+        arguments: OrganizeImportsRequestArgs;
+    }
+
+    export type OrganizeImportsScope = GetCombinedCodeFixScope;
+
+    export interface OrganizeImportsRequestArgs {
+        scope: OrganizeImportsScope;
+    }
+
+    export interface OrganizeImportsResponse extends Response {
+        edits: ReadonlyArray<FileCodeEdits>;
+    }
+
     /**
      * Request for the available codefixes at a specific position.
      */

src/server/protocol.ts

@@ -1597,6 +1597,19 @@ namespace ts.server {
             }
         }
 
+        private organizeImports({ scope }: protocol.OrganizeImportsRequestArgs, simplifiedResult: boolean): ReadonlyArray<protocol.FileCodeEdits> | ReadonlyArray<FileTextChanges> {
+            Debug.assert(scope.type === "file");
+            const { file, project } = this.getFileAndProject(scope.args);
+            const formatOptions = this.projectService.getFormatCodeOptions(file);
+            const changes = project.getLanguageService().organizeImports({ type: "file", fileName: file }, formatOptions);
+            if (simplifiedResult) {
+                return this.mapTextChangesToCodeEdits(project, changes);
+            }
+            else {
+                return changes;
+            }
+        }
+
         private getCodeFixes(args: protocol.CodeFixRequestArgs, simplifiedResult: boolean): ReadonlyArray<protocol.CodeAction> | ReadonlyArray<CodeAction> {
             if (args.errorCodes.length === 0) {
                 return undefined;
@@ -2041,6 +2054,12 @@ namespace ts.server {
             },
             [CommandNames.GetEditsForRefactorFull]: (request: protocol.GetEditsForRefactorRequest) => {
                 return this.requiredResponse(this.getEditsForRefactor(request.arguments, /*simplifiedResult*/ false));
+            },
+            [CommandNames.OrganizeImports]: (request: protocol.OrganizeImportsRequest) => {
+                return this.requiredResponse(this.organizeImports(request.arguments, /*simplifiedResult*/ true));
+            },
+            [CommandNames.OrganizeImportsFull]: (request: protocol.OrganizeImportsRequest) => {
+                return this.requiredResponse(this.organizeImports(request.arguments, /*simplifiedResult*/ false));
             }
         });