[PATCH v6 1/3] t4001: modernize

["Mark C. Chu-Carroll" <markchucarroll@fastmail.com>]

    Old tests were written in a different style than modern
    ones; for better readability and test error messages,
    update t4001 to the modern style.

    * run everything inside of a test_expect_success block.
    * write title line on the same line as test_expect_success,
      end that line with a single quote that opens the body of the test,
      and end the test with a single quote that closes the body.
    * write expected output of a test to a file named "expect",
      and actual output to a file named "actual".
    * write here-docs using "<<-" syntax, so that they're indented
      uniformly with the rest of the test.
    * make test names more clearly reflect the functionality that
      they test.

Signed-off-by: Mark C. Chu-Carroll <markchucarroll@fastmail.com>
---
 t/t4001-diff-rename.sh | 89 ++++++++++++++++++------------------------
 1 file changed, 38 insertions(+), 51 deletions(-)

diff --git a/t/t4001-diff-rename.sh b/t/t4001-diff-rename.sh
index ad474100af..1a2474af10 100755
--- a/t/t4001-diff-rename.sh
+++ b/t/t4001-diff-rename.sh
@@ -26,7 +26,7 @@ test_expect_success 'setup' '
 	Line 14
 	Line 15
 	EOF
-	cat >expected <<-\EOF &&
+	cat >expect <<-\EOF &&
 	diff --git a/path0 b/path1
 	rename from path0
 	rename to path1
@@ -42,7 +42,7 @@ test_expect_success 'setup' '
 	 Line 13
 	 Line 14
 	EOF
-	cat >no-rename <<-\EOF
+	cat >expect-no-rename <<-\EOF &&
 	diff --git a/path0 b/path0
 	deleted file mode 100644
 	index fdbec44..0000000
@@ -86,47 +86,34 @@ test_expect_success 'setup' '
 	+Line 14
 	+Line 15
 	EOF
+	git update-index --add path0
 '
 
-test_expect_success \
-    'update-index --add a file.' \
-    'git update-index --add path0'
-
-test_expect_success \
-    'write that tree.' \
-    'tree=$(git write-tree) && echo $tree'
-
-sed -e 's/line/Line/' <path0 >path1
-rm -f path0
-test_expect_success \
-    'renamed and edited the file.' \
-    'git update-index --add --remove path0 path1'
-
-test_expect_success \
-    'git diff-index -p -M after rename and editing.' \
-    'git diff-index -p -M $tree >current'
-
-
-test_expect_success \
-    'validate the output.' \
-    'compare_diff_patch current expected'
+test_expect_success 'diff shows path0 renamed to path1 with edit' '
+	tree=$(git write-tree) &&
+	sed -e "s/line/Line/" <path0 >path1 &&
+	rm -f path0 &&
+	git update-index --add --remove path0 path1 &&
+	git diff-index -p -M $tree >actual &&
+	compare_diff_patch actual expect
+'
 
-test_expect_success 'test diff.renames=true' '
-	git -c diff.renames=true diff --cached $tree >current &&
-	compare_diff_patch current expected
+test_expect_success 'with diff.renames=true, patch includes rename of path0 to path1' '
+	git -c diff.renames=true diff --cached $tree >actual &&
+	compare_diff_patch actual expect
 '
 
-test_expect_success 'test diff.renames=false' '
-	git -c diff.renames=false diff --cached $tree >current &&
-	compare_diff_patch current no-rename
+test_expect_success 'with diff.renames=false, patch does not include rename' '
+	git -c diff.renames=false diff --cached $tree >actual &&
+	compare_diff_patch actual expect-no-rename
 '
 
-test_expect_success 'test diff.renames unset' '
-	git diff --cached $tree >current &&
-	compare_diff_patch current expected
+test_expect_success 'with no setting for diff.renames, patch includes rename' '
+	git diff --cached $tree >actual &&
+	compare_diff_patch actual expect
 '
 
-test_expect_success 'favour same basenames over different ones' '
+test_expect_success 'diff rename favours same basenames over different ones' '
 	cp path1 another-path &&
 	git add another-path &&
 	git commit -m 1 &&
@@ -137,25 +124,25 @@ test_expect_success 'favour same basenames over different ones' '
 	test_grep "renamed: .*path1 -> subdir/path1" out
 '
 
-test_expect_success 'test diff.renames=true for git status' '
+test_expect_success 'with diff.renames=true, git status includes rename' '
 	git -c diff.renames=true status >out &&
 	test_grep "renamed: .*path1 -> subdir/path1" out
 '
 
-test_expect_success 'test diff.renames=false for git status' '
+test_expect_success 'with diff.renames=false, git status shows delete/add' '
 	git -c diff.renames=false status >out &&
 	test_grep ! "renamed: .*path1 -> subdir/path1" out &&
 	test_grep "new file: .*subdir/path1" out &&
 	test_grep "deleted: .*[^/]path1" out
 '
 
-test_expect_success 'favour same basenames even with minor differences' '
+test_expect_success 'rename logic favours same basenames even with minor differences' '
 	git show HEAD:path1 | sed "s/15/16/" > subdir/path1 &&
 	git status >out &&
 	test_grep "renamed: .*path1 -> subdir/path1" out
 '
 
-test_expect_success 'two files with same basename and same content' '
+test_expect_success 'rename logic favors common path segments for files with the same basename and content' '
 	git reset --hard &&
 	mkdir -p dir/A dir/B &&
 	cp path1 dir/A/file &&
@@ -167,7 +154,7 @@ test_expect_success 'two files with same basename and same content' '
 	test_grep "renamed: .*dir/A/file -> other-dir/A/file" out
 '
 
-test_expect_success 'setup for many rename source candidates' '
+test_expect_success 'rename with many candidates' '
 	git reset --hard &&
 	for i in 0 1 2 3 4 5 6 7 8 9;
 	do
@@ -184,7 +171,7 @@ test_expect_success 'setup for many rename source candidates' '
 	git add new-path path1 &&
 	git diff -l 4 -C -C --cached --name-status >actual 2>actual.err &&
 	sed -e "s/^\([CM]\)[0-9]*	/\1	/" actual >actual.munged &&
-	cat >expect <<-EOF &&
+	cat >expect <<-\EOF &&
 	C	path1	new-path
 	M	path1
 	EOF
@@ -192,7 +179,7 @@ test_expect_success 'setup for many rename source candidates' '
 	test_grep warning actual.err
 '
 
-test_expect_success 'rename pretty print with nothing in common' '
+test_expect_success 'pretty-print paths with nothing in common after rename' '
 	mkdir -p a/b/ &&
 	: >a/b/c &&
 	git add a/b/c &&
@@ -206,7 +193,7 @@ test_expect_success 'rename pretty print with nothing in common' '
 	test_grep " a/b/c => c/b/a " output
 '
 
-test_expect_success 'rename pretty print with common prefix' '
+test_expect_success 'pretty print paths with common prefix after rename' '
 	mkdir -p c/d &&
 	git mv c/b/a c/d/e &&
 	git commit -m "c/b/a -> c/d/e" &&
@@ -216,7 +203,7 @@ test_expect_success 'rename pretty print with common prefix' '
 	test_grep " c/{b/a => d/e} " output
 '
 
-test_expect_success 'rename pretty print with common suffix' '
+test_expect_success 'pretty prints paths with common suffix after rename' '
 	mkdir d &&
 	git mv c/d/e d/e &&
 	git commit -m "c/d/e -> d/e" &&
@@ -226,7 +213,7 @@ test_expect_success 'rename pretty print with common suffix' '
 	test_grep " {c/d => d}/e " output
 '
 
-test_expect_success 'rename pretty print with common prefix and suffix' '
+test_expect_success 'pretty prints paths with common prefix and suffix after rename' '
 	mkdir d/f &&
 	git mv d/e d/f/e &&
 	git commit -m "d/e -> d/f/e" &&
@@ -236,7 +223,7 @@ test_expect_success 'rename pretty print with common prefix and suffix' '
 	test_grep " d/{ => f}/e " output
 '
 
-test_expect_success 'rename pretty print common prefix and suffix overlap' '
+test_expect_success 'pretty prints paths with common prefix and suffix overlap after rename' '
 	mkdir d/f/f &&
 	git mv d/f/e d/f/f/e &&
 	git commit -m "d/f/e d/f/f/e" &&
@@ -261,7 +248,7 @@ test_expect_success 'diff-tree -l0 defaults to a big rename limit, not zero' '
 	test_grep "myotherfile.*myfile" actual
 '
 
-test_expect_success 'basename similarity vs best similarity' '
+test_expect_success 'rename prefers basename similarity over best similarity' '
 	mkdir subdir &&
 	test_write_lines line1 line2 line3 line4 line5 \
 			 line6 line7 line8 line9 line10 >subdir/file.txt &&
@@ -278,14 +265,14 @@ test_expect_success 'basename similarity vs best similarity' '
 	git diff-tree -r -M --name-status HEAD^ HEAD >actual &&
 	# subdir/file.txt is 88% similar to file.md, 78% similar to file.txt,
 	# but since same basenames are checked first...
-	cat >expected <<-\EOF &&
+	cat >expect <<-\EOF &&
 	A	file.md
 	R078	subdir/file.txt	file.txt
 	EOF
-	test_cmp expected actual
+	test_cmp expect actual
 '
 
-test_expect_success 'last line matters too' '
+test_expect_success 'file similarity handles missing trailing newline.' '
 	{
 		test_write_lines a 0 1 2 3 4 5 6 7 8 9 &&
 		printf "git ignores final up to 63 characters if not newline terminated"
@@ -303,10 +290,10 @@ test_expect_success 'last line matters too' '
 	git commit -a -m "rename no-final-lf -> still-absent-final-lf" &&
 	git diff-tree -r -M --name-status HEAD^ HEAD >actual &&
 	sed -e "s/^R[0-9]*	/R	/" actual >actual.munged &&
-	cat >expected <<-\EOF &&
+	cat >expect <<-\EOF &&
 	R	no-final-lf	still-absent-final-lf
 	EOF
-	test_cmp expected actual.munged
+	test_cmp expect actual.munged
 '
 
 test_done
-- 
2.53.0