[Bugfix] Fixes #417 - Force terraform command to apply if a plan file is being used

CHANGELOG.md

@@ -1,6 +1,7 @@
 # Unreleased
 
- - [Issue #432](https://github.com/manheim/terraform-pipeline/issues/432) pass TagPlugin through `-var-file={env}-tags.tfvars`
+- [Issue #432](https://github.com/manheim/terraform-pipeline/issues/432) pass TagPlugin through `-var-file={env}-tags.tfvars`
+- [Issue #417](https://github.com/manheim/terraform-pipeline/issues/417) DestroyPlugin & PassPlanFilePlugin - Terraform Destroy can't be called with a plan file
 
 # v5.19
 

src/TerraformApplyCommand.groovy

@@ -107,7 +107,14 @@ class TerraformApplyCommand implements TerraformCommand, Resettable {
         if (directory && chdir_flag) {
             pieces << "-chdir=${directory}"
         }
-        pieces << command
+        // If we have a plan file, apply is the only command that works.
+        // Even on destroy, you must use `terraform apply` for a plan file
+        // created with the `-destroy` argument.
+        if (planFile) {
+            pieces << "apply"
+        } else {
+            pieces << command
+        }
         if (!input) {
             pieces << "-input=false"
         }

test/TerraformApplyCommandTest.groovy

@@ -236,6 +236,15 @@ class TerraformApplyCommandTest {
             def actualCommand = command.toString()
             assertThat(actualCommand, endsWith(" foobar"))
         }
+
+        @Test
+        void forcesApplyIfPlanFilePresent() {
+            def command = new TerraformApplyCommand().withPlanFile("foobar")
+                                                     .withCommand("destroy")
+
+            def actualCommand = command.toString()
+            assertThat(actualCommand, startsWith("terraform apply"))
+        }
     }
 
     @Nested