Disable some Compose features if Docker's extension is installed (#75)

Docker's extension bundles a language server that provides some Compose
features that overlap with the ones from the Container Tools extension.
Red Hat's YAML extension also does something similar which was
previously accounted for. The code has now been changed to disable
select Compose features if Docker's extension or Red Hat's YAML
extension is installed.

Signed-off-by: Remy Suen <remy.suen@docker.com>

Author: rcjsuen

src/utils/AlternateYamlLanguageServiceClientFeature.ts

@@ -24,20 +24,28 @@ export class AlternateYamlLanguageServiceClientFeature implements StaticFeature,
         };
     }
 
-    public fillClientCapabilities(capabilities: ClientCapabilities): void {
-        // If the RedHat YAML extension is present, we can disable many of the compose language service features
-        if (vscode.extensions.getExtension('redhat.vscode-yaml')) {
-            const altYamlClientCapabilities: AlternateYamlLanguageServiceClientCapabilities = {
-                syntaxValidation: true,
-                schemaValidation: true,
-                basicCompletions: true,
-                advancedCompletions: false, // YAML extension does not have advanced completions for compose docs
-                hover: false, // YAML extension provides hover, but the compose spec lacks descriptions -- https://github.com/compose-spec/compose-spec/issues/138
-                imageLinks: false, // YAML extension does not have image hyperlinks for compose docs
-                serviceStartupCodeLens: false, // YAML extension does not have service startup code lens for compose docs
-                formatting: true,
+    private createAlternateYamlLanguageServiceClientCapabilities(): AlternateYamlLanguageServiceClientCapabilities | null {
+        // If RedHat YAML's extension or Docker's extension is present, we can disable many of the compose language service features
+        const redhat = vscode.extensions.getExtension('redhat.vscode-yaml') !== undefined;
+        const docker = vscode.extensions.getExtension('docker.docker') !== undefined;
+        if (redhat || docker) {
+            return {
+                syntaxValidation: redhat || docker,
+                schemaValidation: redhat,
+                basicCompletions: redhat || docker,
+                advancedCompletions: false, // The other extensions do not have advanced completions for Compose docs
+                hover: redhat || docker, // Compose spec has descriptions
+                imageLinks: docker, // Docker's extension supports Docker Hub, GHCR, MAR, and Quay.io
+                serviceStartupCodeLens: false, // The other extensions do not provide any code lens
+                formatting: redhat || docker,
             };
+        }
+        return null;
+    }
 
+    public fillClientCapabilities(capabilities: ClientCapabilities): void {
+        const altYamlClientCapabilities = this.createAlternateYamlLanguageServiceClientCapabilities();
+        if (altYamlClientCapabilities !== null) {
             capabilities.experimental = {
                 ...capabilities.experimental,
                 alternateYamlLanguageService: altYamlClientCapabilities,