Allow using a different Terraform binary.

In case you're using a different CLI, like `tofu`.

hooks/terraform_fmt.py

@@ -7,16 +7,19 @@ import sys
 import hooks.utils
 
 
+TF_CLI = os.getenv("TF_CLI", "terraform")
+
+
 def main():
     """Main entrypoint."""
     parser = argparse.ArgumentParser(description=__doc__)
     parser.add_argument("file", nargs="+", type=pathlib.Path)
     args = parser.parse_args()
-    hooks.utils.check_executable("terraform")
+    hooks.utils.check_executable(TF_CLI)
     os.putenv("TF_INPUT", "0")
     os.putenv("TF_IN_AUTOMATION", "1")
     return hooks.utils.bulk_check(
-        lambda x: hooks.utils.check_file(["terraform", "fmt", "-diff", x]),
+        lambda x: hooks.utils.check_file([TF_CLI, "fmt", "-diff", x]),
         hooks.utils.unique_directories(args.file),
     )
 

hooks/terraform_validate.py

@@ -7,18 +7,23 @@ import sys
 import hooks.utils
 
 
-def tf_validate(directory):
+TF_CLI = os.getenv("TF_CLI", "terraform")
+
+
+def tf_validate(directory):  # noqa: D213
+    """Validate Terraform modules.
+
+    Also runs init -backend=false to install the providers.
+    """
     if (
         hooks.utils.check_directory(
-            ["terraform", "init", "-backend=false"], directory=directory
+            [TF_CLI, "init", "-backend=false"], directory=directory
         )
         > 0
     ):
         return 1
     if (
-        hooks.utils.check_directory(
-            ["terraform", "validate"], directory=directory
-        )
+        hooks.utils.check_directory([TF_CLI, "validate"], directory=directory)
         > 0
     ):
         return 1