README.rst

@@ -52,10 +52,10 @@ end with :code:`.tfvars`, a :code:`-var-file` argument is added. For example:
 :code:`-var-file=prod/a.tfvars` and :code:`-var-file=prod/b.tfvars`.
 
 By default :code:`tf` invokes :code:`terraform`, but if you're using a
-different tool (like `OpenTofu <https://opentofu.org/>`_ you can set the
-:code:`TF_CLI` environment variable to that tool name. If you wish to know the
-exact command :code:`tf` is running set the :code:`TF_DEBUG` environment
-variable to :code:`1` and the command will printed before the it's invoked.
+different tool (like `OpenTofu <https://opentofu.org/>`_) you can set the
+:code:`TF_CLI` environment variable to that tool's name. If you wish to know
+the exact command :code:`tf` is running set the :code:`TF_DEBUG` environment
+variable to :code:`1` and the command will printed before it's invoked.
 
 License
 -------

tf.py

@@ -83,6 +83,23 @@ def wrapper():
             print(f"Can't find {TF_CLI}.", file=sys.stderr)
             sys.exit(1)
 
+    # We can't add -var-file to an apply command with a plan. So we check all
+    # of the args after the apply arg and if all of them are switches we assume
+    # that a plan isn't specified (technically the plan file can also start
+    # with a "-" and look like a switch, but let's not go there).
+    if command == "apply":
+        apply_index = sys.argv.index("apply")
+        if not all(
+            map(lambda x: x.startswith("-"), sys.argv[apply_index + 1 :])
+        ):
+            # No all args are switches, so a plan is specified and we don't add
+            # the -var-file switch.
+            try:
+                os.execvp(TF_CLI, args)  # nosec
+            except FileNotFoundError:
+                print(f"Can't find {TF_CLI}.", file=sys.stderr)
+                sys.exit(1)
+
     # We need to add the var files after the Terraform command (if we add it
     # before Terraform doesn't accept them) but not at the end (not to modify
     # other argument that accept optional values). So we add them right after