build: automate the 'final' version

Makefile

@@ -176,12 +176,15 @@ sample_html_beta: _sample_cog_html	## Generate sample HTML report for a beta rel
 
 ##@ Kitting: making releases
 
-.PHONY: edit_for_release cheats relbranch relcommit1 relcommit2
+.PHONY: release_version edit_for_release cheats relbranch relcommit1 relcommit2
 .PHONY: kit pypi_upload test_upload kit_local build_kits
 .PHONY: tag bump_version
 
 REPO_OWNER = nedbat/coveragepy
 
+release_version:			#: Update the version for a release.
+	python igor.py release_version
+
 edit_for_release:			#: Edit sources to insert release facts (see howto.txt).
 	python igor.py edit_for_release
 

howto.txt

@@ -3,16 +3,19 @@
 - Check that the current virtualenv matches the current coverage branch.
 - start branch for release work
     $ make relbranch
-- Edit version number in coverage/version.py
+- check version number in coverage/version.py
+    - IF PRE-RELEASE:
+        - edit to look like one of these:
         version_info = (4, 0, 2, "alpha", 1)
         version_info = (4, 0, 2, "beta", 1)
         version_info = (4, 0, 2, "candidate", 1)
         version_info = (4, 0, 2, "final", 0)
-    - make sure: _dev = 0
-- Edit supported Python version numbers. Search for "PYVERSIONS".
-    - Especially README.rst and doc/index.rst
+    - IF NOT PRE-RELEASE:
+        $ make release_version
 - Update source files with release facts, and get useful snippets:
     $ make edit_for_release cheats
+- Edit supported Python version numbers. Search for "PYVERSIONS".
+    - Especially README.rst and doc/index.rst
 - Look over CHANGES.rst
 - Update README.rst
     - "New in x.y:"

igor.py

@@ -419,6 +419,15 @@ def do_edit_for_release():
     )
     update_file("doc/conf.py", r"(?s)# @@@ editable\n.*# @@@ end\n", new_conf)
 
+def do_release_version():
+    """Set the version to 'final' for a release."""
+    facts = get_release_facts()
+    rel_vi = facts.vi[:3] + ("final", 0)
+    rel_version = f"version_info = {rel_vi}\n_dev = 0".replace("'", '"')
+    update_file(
+        "coverage/version.py", r"(?m)^version_info = .*\n_dev = \d+$", rel_version,
+    )
+
 
 def do_bump_version():
     """Edit a few files right after a release to bump the version."""