Deprecate incorrect envFiles task option in favor of envFile

package.json

@@ -1410,6 +1410,10 @@
                                     "type": "string"
                                 }
                             },
+                            "envFile": {
+                                "type": "string",
+                                "description": "%vscode-docker.tasks.docker-compose.dockerCompose.envFile.description%"
+                            },
                             "files": {
                                 "type": "array",
                                 "description": "%vscode-docker.tasks.docker-compose.dockerCompose.files.description%",

package.nls.json

@@ -112,7 +112,8 @@
     "vscode-docker.tasks.docker-compose.dockerCompose.down.removeImages": "Images to remove.",
     "vscode-docker.tasks.docker-compose.dockerCompose.down.removeVolumes": "Whether or not to remove named and anonymous volumes.",
     "vscode-docker.tasks.docker-compose.dockerCompose.down.customOptions": "Any other options to add to the `docker-compose down` command. Cannot be combined with `up`.",
-    "vscode-docker.tasks.docker-compose.dockerCompose.envFiles.description": "Files of environment variables read in and applied to the Docker containers.",
+    "vscode-docker.tasks.docker-compose.dockerCompose.envFiles.description": "(DEPRECATED) Use `envFile` instead.",
+    "vscode-docker.tasks.docker-compose.dockerCompose.envFile.description": "File of environment variables read in and applied to the Docker containers.",
     "vscode-docker.tasks.docker-compose.dockerCompose.files.description": "The docker-compose files to include, in order.",
     "vscode-docker.config.docker.promptForRegistryWhenPushingImages": "Prompt for registry selection if the image is not explicitly tagged.",
     "vscode-docker.config.template.build.template": "The command template.",

src/tasks/DockerComposeTaskDefinitionBase.ts

@@ -26,7 +26,18 @@ export interface DockerComposeDownOptions {
     };
 }
 
-export type DockerComposeOptions = (DockerComposeUpOptions | DockerComposeDownOptions) & { envFiles?: string[], files?: string[] };
+export interface DockerComposeUpAndDownOptions {
+    envFile?: string;
+
+    /**
+     * @deprecated Use `envFile` instead
+     */
+    envFiles?: string[];
+
+    files?: string[];
+}
+
+export type DockerComposeOptions = (DockerComposeUpOptions | DockerComposeDownOptions) & DockerComposeUpAndDownOptions;
 
 export interface DockerComposeTaskDefinitionBase extends TaskDefinitionBase {
     dockerCompose?: DockerComposeOptions;

src/tasks/DockerComposeTaskProvider.ts

@@ -29,7 +29,10 @@ export class DockerComposeTaskProvider extends DockerTaskProvider {
         const definition = cloneObject(task.definition);
         definition.dockerCompose = definition.dockerCompose || {};
         definition.dockerCompose.files = definition.dockerCompose.files || [];
-        definition.dockerCompose.envFiles = definition.dockerCompose.envFiles || [];
+
+        // Fix wrong environment file option name
+        definition.dockerCompose.envFile = this.normalizeEnvFile(definition.dockerCompose);
+        definition.dockerCompose.envFiles = undefined;
 
         await this.validateResolvedDefinition(context, definition.dockerCompose);
 
@@ -66,10 +69,8 @@ export class DockerComposeTaskProvider extends DockerTaskProvider {
             }
         }
 
-        for (const file of dockerCompose.envFiles) {
-            if (!(await fse.pathExists(path.resolve(context.folder.uri.fsPath, resolveVariables(file, context.folder))))) {
-                throw new Error(localize('vscode-docker.tasks.composeProvider.invalidEnvFile', 'One or more environment files does not exist or could not be accessed.'));
-            }
+        if (dockerCompose.envFile && !(await fse.pathExists(path.resolve(context.folder.uri.fsPath, resolveVariables(dockerCompose.envFile, context.folder))))) {
+            throw new Error(localize('vscode-docker.tasks.composeProvider.invalidEnvFile', 'Environment file does not exist or could not be accessed.'));
         }
     }
 
@@ -87,7 +88,7 @@ export class DockerComposeTaskProvider extends DockerTaskProvider {
             return CommandLineBuilder
                 .create(await getComposeCliCommand())
                 .withArrayArgs('-f', options.files)
-                .withArrayArgs('--env-file', options.envFiles)
+                .withNamedArg('--env-file', options.envFile)
                 .withArrayArgs('--profile', options.up.profiles)
                 .withArg('up')
                 .withFlagArg('--detach', !!options.up.detached)
@@ -100,11 +101,24 @@ export class DockerComposeTaskProvider extends DockerTaskProvider {
             return CommandLineBuilder
                 .create(await getComposeCliCommand())
                 .withArrayArgs('-f', options.files)
-                .withArrayArgs('--env-file', options.envFiles)
+                .withNamedArg('--env-file', options.envFile)
                 .withArg('down')
                 .withNamedArg('--rmi', options.down.removeImages)
                 .withFlagArg('--volumes', options.down.removeVolumes)
                 .withArg(options.down.customOptions);
         }
     }
+
+    private normalizeEnvFile(options: DockerComposeOptions): string {
+        if (options.envFile) {
+            // If the new option is specified, always use it
+            return options.envFile;
+        } else if (options.envFiles?.length) {
+            // Otherwise use the old option if it is specified
+            // Compose' behavior is to ignore all prior entries and use only the last environment file
+            return options.envFiles[options.envFiles.length - 1];
+        } else {
+            return undefined;
+        }
+    }
 }