Change -force to -auto-approve when destroying

Since an early version of Terraform, the `destroy` command has always
had the `-force` flag to allow an auto approval of the interactive
prompt. 0.11 introduced `-auto-approve` as default to `false` when using
the `apply` command.

The `-auto-approve` flag was introduced to reduce ambiguity of it's
function, but the `-force` flag was never updated for a destroy.

People often use wrappers when automating commands in Terraform, and the
inconsistency between `apply` and `destroy` means that additional logic
must be added to the wrappers to do similar functions. Both commands are
more or less able to run with similar syntax, and also heavily share
their code.

This commit updates the command in `destroy` to use the `-auto-approve` flag
making working with the Terraform CLI a more consistent experience.

We leave in `-force` in `destroy` for the time-being and flag it as
deprecated to ensure a safe switchover period.

backend/local/backend_apply.go

@@ -99,7 +99,7 @@ func (b *Local) opApply(
 		dispPlan := format.NewPlan(plan)
 		trivialPlan := dispPlan.Empty()
 		hasUI := op.UIOut != nil && op.UIIn != nil
-		mustConfirm := hasUI && ((op.Destroy && !op.DestroyForce) || (!op.Destroy && !op.AutoApprove && !trivialPlan))
+		mustConfirm := hasUI && ((op.Destroy && (!op.DestroyForce && !op.AutoApprove)) || (!op.Destroy && !op.AutoApprove && !trivialPlan))
 		if mustConfirm {
 			var desc, query string
 			if op.Destroy {

command/apply.go

@@ -40,13 +40,11 @@ func (c *ApplyCommand) Run(args []string) int {
 	}
 
 	cmdFlags := c.Meta.flagSet(cmdName)
+	cmdFlags.BoolVar(&autoApprove, "auto-approve", false, "skip interactive approval of plan before applying")
 	if c.Destroy {
-		cmdFlags.BoolVar(&destroyForce, "force", false, "force")
+		cmdFlags.BoolVar(&destroyForce, "force", false, "deprecated: same as auto-approve")
 	}
 	cmdFlags.BoolVar(&refresh, "refresh", true, "refresh")
-	if !c.Destroy {
-		cmdFlags.BoolVar(&autoApprove, "auto-approve", false, "skip interactive approval of plan before applying")
-	}
 	cmdFlags.IntVar(
 		&c.Meta.parallelism, "parallelism", DefaultParallelism, "parallelism")
 	cmdFlags.StringVar(&c.Meta.statePath, "state", "", "path")
@@ -250,8 +248,6 @@ Options:
 
   -lock-timeout=0s       Duration to retry a state lock.
 
-  -auto-approve          Skip interactive approval of plan before applying.
-
   -input=true            Ask for input for variables if not directly set.
 
   -no-color              If specified, output won't contain any color.
@@ -297,7 +293,9 @@ Options:
                          modifying. Defaults to the "-state-out" path with
                          ".backup" extension. Set to "-" to disable backup.
 
-  -force                 Don't ask for input for destroy confirmation.
+  -auto-approve          Skip interactive approval before destroying.
+
+  -force                 Deprecated: same as auto-approve.
 
   -lock=true             Lock the state file when locking is supported.
 

command/apply_destroy_test.go

@@ -40,7 +40,7 @@ func TestApply_destroy(t *testing.T) {
 
 	// Run the apply command pointing to our existing state
 	args := []string{
-		"-force",
+		"-auto-approve",
 		"-state", statePath,
 		testFixturePath("apply"),
 	}
@@ -130,7 +130,7 @@ func TestApply_destroyLockedState(t *testing.T) {
 
 	// Run the apply command pointing to our existing state
 	args := []string{
-		"-force",
+		"-auto-approve",
 		"-state", statePath,
 		testFixturePath("apply"),
 	}
@@ -206,7 +206,7 @@ func TestApply_destroyTargeted(t *testing.T) {
 
 	// Run the apply command pointing to our existing state
 	args := []string{
-		"-force",
+		"-auto-approve",
 		"-target", "test_instance.foo",
 		"-state", statePath,
 		testFixturePath("apply-destroy-targeted"),

command/e2etest/primary_test.go

@@ -111,7 +111,7 @@ func TestPrimarySeparatePlan(t *testing.T) {
 	}
 
 	//// DESTROY
-	stdout, stderr, err = tf.Run("destroy", "-force")
+	stdout, stderr, err = tf.Run("destroy", "-auto-approve")
 	if err != nil {
 		t.Fatalf("unexpected destroy error: %s\nstderr:\n%s", err, stderr)
 	}

website/docs/commands/destroy.html.markdown

@@ -22,7 +22,7 @@ This command accepts all the arguments and flags that the [apply
 command](/docs/commands/apply.html) accepts, with the exception of a plan file
 argument.
 
-If `-force` is set, then the destroy confirmation will not be shown.
+If `-auto-approve` is set, then the destroy confirmation will not be shown.
 
 The `-target` flag, instead of affecting "dependencies" will instead also
 destroy any resources that _depend on_ the target(s) specified.