command: test `get` with const variables

internal/command/get_test.go

@@ -8,6 +8,10 @@ import (
 	"testing"
 
 	"github.com/hashicorp/cli"
+
+	"github.com/hashicorp/terraform/internal/backend"
+	backendInit "github.com/hashicorp/terraform/internal/backend/init"
+	backendCloud "github.com/hashicorp/terraform/internal/cloud"
 )
 
 func TestGet(t *testing.T) {
@@ -113,3 +117,89 @@ func TestGet_cancel(t *testing.T) {
 		t.Fatalf("wrong error message\nshould contain: %s\ngot:\n%s", want, got)
 	}
 }
+
+func TestGet_constVariable(t *testing.T) {
+	// Scenario 1: no value for variable -> diagnostic
+	t.Run("missing value", func(t *testing.T) {
+		wd := tempWorkingDirFixture(t, "dynamic-module-sources/get-const-var")
+		t.Chdir(wd.RootModuleDir())
+
+		ui := cli.NewMockUi()
+		c := &GetCommand{
+			Meta: Meta{
+				testingOverrides: metaOverridesForProvider(testProvider()),
+				Ui:               ui,
+				WorkingDir:       wd,
+			},
+		}
+
+		args := []string{}
+		if code := c.Run(args); code == 0 {
+			t.Fatalf("expected error, got 0")
+		}
+
+		errStr := ui.ErrorWriter.String()
+		if !strings.Contains(errStr, "No value for required variable") {
+			t.Fatalf("expected missing variable error, got: %s", errStr)
+		}
+	})
+
+	// Scenario 2: value via cli -> works
+	t.Run("value via cli", func(t *testing.T) {
+		wd := tempWorkingDirFixture(t, "dynamic-module-sources/get-const-var")
+		t.Chdir(wd.RootModuleDir())
+
+		ui := cli.NewMockUi()
+		c := &GetCommand{
+			Meta: Meta{
+				testingOverrides: metaOverridesForProvider(testProvider()),
+				Ui:               ui,
+				WorkingDir:       wd,
+			},
+		}
+
+		args := []string{"-var", "module_name=example"}
+		if code := c.Run(args); code != 0 {
+			t.Fatalf("bad: \n%s", ui.ErrorWriter.String())
+		}
+
+		output := ui.OutputWriter.String()
+		if !strings.Contains(output, "- example in") {
+			t.Fatalf("doesn't look like get: %s", output)
+		}
+	})
+
+	// Scenario 3: value via backend
+	t.Run("value via backend", func(t *testing.T) {
+		server := cloudTestServerWithVars(t)
+		defer server.Close()
+		d := testDisco(server)
+
+		previousBackend := backendInit.Backend("cloud")
+		backendInit.Set("cloud", func() backend.Backend { return backendCloud.New(d) })
+		defer backendInit.Set("cloud", previousBackend)
+
+		wd := tempWorkingDirFixture(t, "dynamic-module-sources/get-const-var-backend")
+		t.Chdir(wd.RootModuleDir())
+
+		ui := cli.NewMockUi()
+		c := &GetCommand{
+			Meta: Meta{
+				testingOverrides: metaOverridesForProvider(testProvider()),
+				Ui:               ui,
+				WorkingDir:       wd,
+				Services:         d,
+			},
+		}
+
+		args := []string{}
+		if code := c.Run(args); code != 0 {
+			t.Fatalf("bad: \n%s", ui.ErrorWriter.String())
+		}
+
+		output := ui.OutputWriter.String()
+		if !strings.Contains(output, "- example in") {
+			t.Fatalf("doesn't look like get: %s", output)
+		}
+	})
+}

internal/command/testdata/dynamic-module-sources/get-const-var-backend/.terraform/terraform.tfstate

@@ -0,0 +1,18 @@
+{
+  "version": 3,
+  "terraform_version": "1.15.0",
+  "backend": {
+    "type": "cloud",
+    "config": {
+      "hostname": null,
+      "organization": "hashicorp",
+      "token": null,
+      "workspaces": {
+        "name": "test",
+        "project": null,
+        "tags": null
+      }
+    },
+    "hash": 1816475682
+  }
+}

internal/command/testdata/dynamic-module-sources/get-const-var-backend/main.tf

@@ -0,0 +1,17 @@
+terraform {
+  cloud {
+    organization = "hashicorp"
+    workspaces {
+      name = "test"
+    }
+  }
+}
+
+variable "module_name" {
+  type  = string
+  const = true
+}
+
+module "example" {
+  source = "./modules/${var.module_name}"
+}

internal/command/testdata/dynamic-module-sources/get-const-var-backend/modules/example/empty.tf

@@ -0,0 +1 @@
+// Empty

internal/command/testdata/dynamic-module-sources/get-const-var/main.tf

@@ -0,0 +1,8 @@
+variable "module_name" {
+  type  = string
+  const = true
+}
+
+module "example" {
+  source = "./modules/${var.module_name}"
+}

internal/command/testdata/dynamic-module-sources/get-const-var/modules/example/empty.tf

@@ -0,0 +1 @@
+// Empty