Merge branch 'pw/diff-color-moved-fix'

Correctness and performance update to "diff --color-moved" feature.

* pw/diff-color-moved-fix:
  diff --color-moved: intern strings
  diff: use designated initializers for emitted_diff_symbol
  diff --color-moved-ws=allow-indentation-change: improve hash lookups
  diff --color-moved: stop clearing potential moved blocks
  diff --color-moved: shrink potential moved blocks as we go
  diff --color-moved: unify moved block growth functions
  diff --color-moved: call comparison function directly
  diff --color-moved-ws=allow-indentation-change: simplify and optimize
  diff: simplify allow-indentation-change delta calculation
  diff --color-moved: avoid false short line matches and bad zebra coloring
  diff --color-moved=zebra: fix alternate coloring
  diff --color-moved: rewind when discarding pmb
  diff --color-moved: factor out function
  diff --color-moved: clear all flags on blocks that are too short
  diff --color-moved: add perf tests

1 files changed, 57 insertions, 0 deletions

diff --git a/t/perf/p4002-diff-color-moved.sh b/t/perf/p4002-diff-color-moved.sh
new file mode 100755
index 0000000..ab2af93
--- /dev/null
+++ b/t/perf/p4002-diff-color-moved.sh
@@ -0,0 +1,57 @@
+#!/bin/sh
+
+test_description='Tests diff --color-moved performance'
+. ./perf-lib.sh
+
+test_perf_default_repo
+
+# The endpoints of the diff can be customized by setting TEST_REV_A
+# and TEST_REV_B in the environment when running this test.
+
+rev="${TEST_REV_A:-v2.28.0}"
+if ! rev_a="$(git rev-parse --quiet --verify "$rev")"
+then
+	skip_all="skipping because '$rev' was not found. \
+		  Use TEST_REV_A and TEST_REV_B to set the revs to use"
+	test_done
+fi
+rev="${TEST_REV_B:-v2.29.0}"
+if ! rev_b="$(git rev-parse --quiet --verify "$rev")"
+then
+	skip_all="skipping because '$rev' was not found. \
+		  Use TEST_REV_A and TEST_REV_B to set the revs to use"
+	test_done
+fi
+
+GIT_PAGER_IN_USE=1
+test_export GIT_PAGER_IN_USE rev_a rev_b
+
+test_perf 'diff --no-color-moved --no-color-moved-ws large change' '
+	git diff --no-color-moved --no-color-moved-ws $rev_a $rev_b
+'
+
+test_perf 'diff --color-moved --no-color-moved-ws large change' '
+	git diff --color-moved=zebra --no-color-moved-ws $rev_a $rev_b
+'
+
+test_perf 'diff --color-moved-ws=allow-indentation-change large change' '
+	git diff --color-moved=zebra --color-moved-ws=allow-indentation-change \
+		$rev_a $rev_b
+'
+
+test_perf 'log --no-color-moved --no-color-moved-ws' '
+	git log --no-color-moved --no-color-moved-ws --no-merges --patch \
+		-n1000 $rev_b
+'
+
+test_perf 'log --color-moved --no-color-moved-ws' '
+	git log --color-moved=zebra --no-color-moved-ws --no-merges --patch \
+		-n1000 $rev_b
+'
+
+test_perf 'log --color-moved-ws=allow-indentation-change' '
+	git log --color-moved=zebra --color-moved-ws=allow-indentation-change \
+		--no-merges --patch -n1000 $rev_b
+'
+
+test_done