Added omnisharp.enableMsBuildLoadProjectsOnDemand to allow enabling f…

…eature OmniSharp/omnisharp-roslyn#1322

package.json

@@ -675,6 +675,11 @@
           "default": false,
           "description": "Specifies whether notifications should be shown if OmniSharp encounters warnings or errors loading a project. Note that these warnings/errors are always emitted to the OmniSharp log"
         },
+        "omnisharp.enableMsBuildLoadProjectsOnDemand": {
+          "type": "boolean",
+          "default": false,
+          "description": "If true, MSBuild project system will only be loading projects for files that were opened in the editor. This setting is useful for big C# codebases and allows for faster initialization of code navigation features only for projects that are relevant to code that is being edited. The downside of enabling this setting is that potentially a limited semantic information is available to OmniSharp extension which for example can manifest itself in incomplete number of references shown for a symbol."
+        },
         "razor.plugin.path": {
           "type": [
             "string",

src/observers/OptionChangeObserver.ts

@@ -33,5 +33,6 @@ export function ShowOmniSharpConfigChangePrompt(optionObservable: Observable<Opt
 function hasChanged(oldOptions: Options, newOptions: Options): boolean {
     return (oldOptions.path != newOptions.path ||
         oldOptions.useGlobalMono != newOptions.useGlobalMono ||
+        oldOptions.enableMsBuildLoadProjectsOnDemand != newOptions.enableMsBuildLoadProjectsOnDemand ||
         oldOptions.waitForDebugger != newOptions.waitForDebugger);
 }

src/omnisharp/options.ts

@@ -24,6 +24,7 @@ export class Options {
         public maxFindSymbolsItems: number,
         public razorDisabled: boolean,
         public razorDevMode: boolean,
+        public enableMsBuildLoadProjectsOnDemand: boolean,
         public razorPluginPath?: string,
         public defaultLaunchSolution?: string,
         public monoPath?: string,
@@ -73,6 +74,8 @@ export class Options {
         const minFindSymbolsFilterLength = omnisharpConfig.get<number>('minFindSymbolsFilterLength', 0);
         const maxFindSymbolsItems = omnisharpConfig.get<number>('maxFindSymbolsItems', 1000);   // The limit is applied only when this setting is set to a number greater than zero
 
+        const enableMsBuildLoadProjectsOnDemand = omnisharpConfig.get<boolean>('enableMsBuildLoadProjectsOnDemand', false);
+
         const razorDisabled = !!razorConfig && razorConfig.get<boolean>('disabled', false);
         const razorDevMode = !!razorConfig && razorConfig.get<boolean>('devmode', false);
         const razorPluginPath = razorConfig ? razorConfig.get<string>('plugin.path', undefined) : undefined;
@@ -97,6 +100,7 @@ export class Options {
             maxFindSymbolsItems,
             razorDisabled,
             razorDevMode,
+            enableMsBuildLoadProjectsOnDemand,
             razorPluginPath,
             defaultLaunchSolution,
             monoPath,

src/omnisharp/server.ts

@@ -317,6 +317,10 @@ export class OmniSharpServer {
             args.push('--debug');
         }
 
+        if (options.enableMsBuildLoadProjectsOnDemand === true) {
+            args.push('MsBuild:LoadProjectsOnDemand=true');
+        }
+
         let launchInfo: LaunchInfo;
         try {
             launchInfo = await this._omnisharpManager.GetOmniSharpLaunchInfo(this.packageJSON.defaults.omniSharp, options.path, serverUrl, latestVersionFileServerPath, installPath, this.extensionPath);

test/unitTests/Fakes/FakeOptions.ts

@@ -6,5 +6,5 @@
 import { Options } from "../../../src/omnisharp/options";
 
 export function getEmptyOptions(): Options {
-    return new Options("", "", false, "", false, 0, 0, false, false, false, false, false, false, 0, 0, false, false, undefined, "", "");
+    return new Options("", "", false, "", false, 0, 0, false, false, false, false, false, false, 0, 0, false, false, false, undefined, "", "");
 }

test/unitTests/OptionObserver/OptionChangeObserver.test.ts

@@ -41,6 +41,7 @@ suite("OmniSharpConfigChangeObserver", () => {
     [
         { config: "omnisharp", section: "path", value: "somePath" },
         { config: "omnisharp", section: "waitForDebugger", value: true },
+        { config: "omnisharp", section: "enableMsBuildLoadProjectsOnDemand", value: true },
         { config: "omnisharp", section: "useGlobalMono", value: "always" }
 
     ].forEach(elem => {

test/unitTests/optionStream.test.ts

@@ -51,7 +51,8 @@ suite('OptionStream', () => {
             options.disableCodeActions.should.equal(false);
             options.minFindSymbolsFilterLength.should.equal(0);
             options.maxFindSymbolsItems.should.equal(1000);
-                expect(options.defaultLaunchSolution).to.be.undefined;
+            options.enableMsBuildLoadProjectsOnDemand.should.equal(false);
+            expect(options.defaultLaunchSolution).to.be.undefined;
         });
 
         test('Gives the changed option when the omnisharp config changes', () => {

test/unitTests/options.test.ts

@@ -30,6 +30,7 @@ suite("Options tests", () => {
         options.disableCodeActions.should.equal(false);
         options.minFindSymbolsFilterLength.should.equal(0);
         options.maxFindSymbolsItems.should.equal(1000);
+        options.enableMsBuildLoadProjectsOnDemand.should.equal(false);
         expect(options.defaultLaunchSolution).to.be.undefined;
     });