[WIP] backend/enhanced: start with absolute configuration path

backend/remote/backend_plan.go

@@ -138,11 +138,18 @@ func (b *Remote) plan(stopCtx, cancelCtx context.Context, op *backend.Operation,
 
 	var configDir string
 	if op.ConfigDir != "" {
+		// De-normalize the configuration directory path.
+		configDir, err = filepath.Abs(op.ConfigDir)
+		if err != nil {
+			return nil, generalError(
+				"Failed to get absolute path of the configuration directory: %v", err)
+		}
+
 		// Make sure to take the working directory into account by removing
 		// the working directory from the current path. This will result in
 		// a path that points to the expected root of the workspace.
 		configDir = filepath.Clean(strings.TrimSuffix(
-			filepath.Clean(op.ConfigDir),
+			filepath.Clean(configDir),
 			filepath.Clean(w.WorkingDirectory),
 		))
 	} else {

backend/remote/backend_plan_test.go

@@ -622,7 +622,7 @@ func TestRemote_planWithWorkingDirectory(t *testing.T) {
 		WorkingDirectory: tfe.String("terraform"),
 	}
 
-	// Configure the workspace to use a custom working direcrtory.
+	// Configure the workspace to use a custom working directory.
 	_, err := b.client.Workspaces.Update(context.Background(), b.organization, b.workspace, options)
 	if err != nil {
 		t.Fatalf("error configuring working directory: %v", err)
@@ -655,6 +655,61 @@ func TestRemote_planWithWorkingDirectory(t *testing.T) {
 	}
 }
 
+func TestRemote_planWithWorkingDirectoryFromCurrentPath(t *testing.T) {
+	b, bCleanup := testBackendDefault(t)
+	defer bCleanup()
+
+	options := tfe.WorkspaceUpdateOptions{
+		WorkingDirectory: tfe.String("terraform"),
+	}
+
+	// Configure the workspace to use a custom working directory.
+	_, err := b.client.Workspaces.Update(context.Background(), b.organization, b.workspace, options)
+	if err != nil {
+		t.Fatalf("error configuring working directory: %v", err)
+	}
+
+	wd, err := os.Getwd()
+	if err != nil {
+		t.Fatalf("error getting current working directory: %v", err)
+	}
+
+	// We need to change into the configuration directory to make sure
+	// the logic to upload the correct slug is working as expected.
+	if err := os.Chdir("./testdata/plan-with-working-directory/terraform"); err != nil {
+		t.Fatalf("error changing directory: %v", err)
+	}
+	defer os.Chdir(wd) // Make sure we change back again when were done.
+
+	// For this test we need to give our current directory instead of the
+	// full path to the configuration as we already changed directories.
+	op, configCleanup := testOperationPlan(t, ".")
+	defer configCleanup()
+
+	op.Workspace = backend.DefaultStateName
+
+	run, err := b.Operation(context.Background(), op)
+	if err != nil {
+		t.Fatalf("error starting operation: %v", err)
+	}
+
+	<-run.Done()
+	if run.Result != backend.OperationSuccess {
+		t.Fatalf("operation failed: %s", b.CLI.(*cli.MockUi).ErrorWriter.String())
+	}
+	if run.PlanEmpty {
+		t.Fatalf("expected a non-empty plan")
+	}
+
+	output := b.CLI.(*cli.MockUi).OutputWriter.String()
+	if !strings.Contains(output, "Running plan in the remote backend") {
+		t.Fatalf("expected remote backend header in output: %s", output)
+	}
+	if !strings.Contains(output, "1 to add, 0 to change, 0 to destroy") {
+		t.Fatalf("expected plan summery in output: %s", output)
+	}
+}
+
 func TestRemote_planPolicyPass(t *testing.T) {
 	b, bCleanup := testBackendDefault(t)
 	defer bCleanup()