Re: [PATCH] t6016: move to lib-log-graph.sh framework

Abhishek Kumar [off-list ref] writes:

On Sun, Jan 03, 2021 at 07:30:35PM -0700, Antonio Russo wrote:

quoted

t6016 manually reconstructs git log --graph output by using the reported
commit hashes from `git rev-parse`.  Each tag is converted into an
environment variable manually, and then `echo`-ed to an expected output
file, which is in turn compared to the actual output.

The expected output is difficult to read and write, because, e.g.,
each line of output must be prefaced with echo, quoted, and properly
escaped.  Additionally, the test is sensitive to trailing whitespace,
which may potentially be removed from graph log output in the future.

In order to reduce duplication, ease troubleshooting of failed tests by
improving readability, and ease the addition of more tests to this file,
port the operations to `lib-log-graph.sh`, which is already used in
several other tests, e.g., t4215.  Give all merges a simple commit
message, and use a common `check_graph` macro taking a heredoc of the
expected output which does not required extensive escaping.

Glad to see others using `lib-log-graph.sh` as well!

The changes look alright to me but maybe you could have split the two
changes into two different commits: Using tags directly instead of
environment variables and using `check_graph` instead of manually
`echo`-ing to an expected output and comparing with the actual output.

Perhaps.  Also I am wondering if the tests still need to create tags
after this change---isn't the output all matched by the commit title
now?

That is ...

quoted

 . ./test-lib.sh
+. "$TEST_DIRECTORY"/lib-log-graph.sh
+
+check_graph () {
+	cat >expect &&
+	lib_test_cmp_graph --format=%s "$@"
+}

... this only shows the title, and ...

quoted

-	git merge B C &&
+	git merge B C -m A4 &&

... that is why we need to have the title here.

quoted

 	git tag A4 &&

Now, does this A4 used anywhere?

quoted

-	# Store commit names in variables for later use
-	A1=$(git rev-parse --verify A1) &&
-	A2=$(git rev-parse --verify A2) &&
-	A3=$(git rev-parse --verify A3) &&
-	A4=$(git rev-parse --verify A4) &&

It certainly used to be needed here, but ...

quoted

+	check_graph --all <<-\EOF
+	* A7
+	*   A6
+	|\
+	| * C4
+	| * C3
+	* | A5
+	| |
+	|  \
+	*-. | A4

... not anymore in the new version.

quoted

+	|\ \|
+	| | * C2
+	| | * C1
+	| * | B2
+	| * | B1
+	* | | A3
+	| |/
+	|/|
+	* | A2
+	|/
+	* A1
+	EOF
+'