1 files changed, 41 insertions, 0 deletions
diff --git a/subplot/bumper.py b/subplot/bumper.py
index 66d2564..0e6a0ef 100644
--- a/subplot/bumper.py
+++ b/subplot/bumper.py
@@ -1,4 +1,6 @@
+import logging
 import os
+import shlex
 
 
 def install_bumper(ctx):
@@ -7,3 +9,42 @@ def install_bumper(ctx):
 
     # Add the directory with built Rust binaries to the path.
     runcmd_prepend_to_path(ctx, dirname=os.path.join(srcdir, "target", "debug"))
+
+
+def git_init_and_commit_everything(ctx, dirname=None):
+    runcmd_run = globals()["runcmd_run"]
+    runcmd_run(ctx, ["git", "init", dirname])
+    runcmd_run(ctx, ["git", "add", "."], cwd=dirname)
+    runcmd_run(ctx, ["git", "commit", "-minitial"], cwd=dirname)
+
+
+def remember_HEAD(ctx, dirname=None, varname=None):
+    runcmd_run = globals()["runcmd_run"]
+    runcmd_get_stdout = globals()["runcmd_get_stdout"]
+    runcmd_run(ctx, ["git", "rev-parse", "HEAD"], cwd=dirname)
+    ctx[varname] = runcmd_get_stdout(ctx).strip()
+
+
+def run_command_in_directory(ctx, dirname=None, argv0=None, args=None):
+    runcmd_run = globals()["runcmd_run"]
+    runcmd_exit_code_is_zero = globals()["runcmd_exit_code_is_zero"]
+
+    argv = [shlex.quote(argv0)] + shlex.split(args)
+    runcmd_run(ctx, argv, cwd=dirname)
+    runcmd_exit_code_is_zero(ctx)
+
+
+def git_tag_points_at(ctx, dirname=None, tag=None, varname=None):
+    runcmd_run = globals()["runcmd_run"]
+    runcmd_get_stdout = globals()["runcmd_get_stdout"]
+    runcmd_exit_code_is_zero = globals()["runcmd_exit_code_is_zero"]
+
+    runcmd_run(ctx, ["git", "show", "--raw", tag], cwd=dirname)
+    runcmd_exit_code_is_zero(ctx)
+
+    output = runcmd_get_stdout(ctx)
+    commit = ctx[varname]
+    logging.debug(f"expecting tag {tag} to point at {commit}")
+    logging.debug(f"tag: {output!r}")
+    assert output.startswith(f"tag {tag}\n")
+    assert f"\ncommit {commit}" in output