[PATCH 2/2] t: add -I<regex> tests

["Michał Kępień" <michal@isc.org>]

Exercise the new 'git diff -I<regex>' option in various scenarios to
ensure it behaves as expected.

Signed-off-by: Michał Kępień <michal@isc.org>
---
 t/t4069-diff-ignore-regex.sh | 330 +++++++++++++++++++++++++++++++++++
 1 file changed, 330 insertions(+)
 create mode 100755 t/t4069-diff-ignore-regex.sh

diff --git a/t/t4069-diff-ignore-regex.sh b/t/t4069-diff-ignore-regex.sh
new file mode 100755
index 0000000000..323687f1dc
--- /dev/null
+++ b/t/t4069-diff-ignore-regex.sh
@@ -0,0 +1,330 @@
+#!/bin/sh
+
+test_description='Test diff -I<regex>'
+
+. ./test-lib.sh
+. "$TEST_DIRECTORY"/diff-lib.sh
+
+test_expect_success setup '
+	test_seq 20 >x &&
+	git update-index --add x
+'
+
+test_expect_success 'one line changed' '
+	test_seq 20 | sed "s/10/100/" >x &&
+
+	# Get plain diff
+	git diff >plain &&
+	cat >expected <<-EOF &&
+	diff --git a/x b/x
+	--- a/x
+	+++ b/x
+	@@ -7,7 +7,7 @@
+	 7
+	 8
+	 9
+	-10
+	+100
+	 11
+	 12
+	 13
+	EOF
+	compare_diff_patch expected plain &&
+
+	# Both old and new line match regex - ignore change
+	git diff -I "^10" >actual &&
+	test_must_be_empty actual &&
+
+	# Only old line matches regex - do not ignore change
+	git diff -I "^10\$" >actual &&
+	compare_diff_patch plain actual &&
+
+	# Only new line matches regex - do not ignore change
+	git diff -I "^100" >actual &&
+	compare_diff_patch plain actual
+'
+
+test_expect_success 'one line removed' '
+	test_seq 20 | sed "10d" >x &&
+
+	# Get plain diff
+	git diff >plain &&
+	cat >expected <<-EOF &&
+	diff --git a/x b/x
+	--- a/x
+	+++ b/x
+	@@ -7,7 +7,6 @@
+	 7
+	 8
+	 9
+	-10
+	 11
+	 12
+	 13
+	EOF
+	compare_diff_patch expected plain &&
+
+	# Removed line matches regex - ignore change
+	git diff -I "^10" >actual &&
+	test_must_be_empty actual &&
+
+	# Removed line does not match regex - do not ignore change
+	git diff -I "^101" >actual &&
+	compare_diff_patch plain actual
+'
+
+test_expect_success 'one line added' '
+	test_seq 21 >x &&
+
+	# Get plain diff
+	git diff >plain &&
+	cat >expected <<-EOF &&
+	diff --git a/x b/x
+	--- a/x
+	+++ b/x
+	@@ -18,3 +18,4 @@
+	 18
+	 19
+	 20
+	+21
+	EOF
+	compare_diff_patch expected plain &&
+
+	# Added line matches regex - ignore change
+	git diff -I "^21" >actual &&
+	test_must_be_empty actual &&
+
+	# Added line does not match regex - do not ignore change
+	git diff -I "^212" >actual &&
+	compare_diff_patch plain actual
+'
+
+test_expect_success 'last two lines changed' '
+	test_seq 20 | sed "s/19/21/; s/20/22/" >x &&
+
+	# Get plain diff
+	git diff >plain &&
+	cat >expected <<-EOF &&
+	diff --git a/x b/x
+	--- a/x
+	+++ b/x
+	@@ -16,5 +16,5 @@
+	 16
+	 17
+	 18
+	-19
+	-20
+	+21
+	+22
+	EOF
+	compare_diff_patch expected plain &&
+
+	# All changed lines match regex - ignore change
+	git diff -I "^[12]" >actual &&
+	test_must_be_empty actual &&
+
+	# Not all changed lines match regex - do not ignore change
+	git diff -I "^2" >actual &&
+	compare_diff_patch plain actual
+'
+
+test_expect_success 'two non-adjacent lines removed in the same hunk' '
+	test_seq 20 | sed "1d; 3d" >x &&
+
+	# Get plain diff
+	git diff >plain &&
+	cat >expected <<-EOF &&
+	diff --git a/x b/x
+	--- a/x
+	+++ b/x
+	@@ -1,6 +1,4 @@
+	-1
+	 2
+	-3
+	 4
+	 5
+	 6
+	EOF
+	compare_diff_patch expected plain &&
+
+	# Both removed lines match regex - ignore hunk
+	git diff -I "^[1-3]" >actual &&
+	test_must_be_empty actual &&
+
+	# First removed line does not match regex - do not ignore hunk
+	git diff -I "^[2-3]" >actual &&
+	compare_diff_patch plain actual &&
+
+	# Second removed line does not match regex - do not ignore hunk
+	git diff -I "^[1-2]" >actual &&
+	compare_diff_patch plain actual
+'
+
+test_expect_success 'two non-adjacent lines removed in the same hunk, with -U1' '
+	test_seq 20 | sed "1d; 3d" >x &&
+
+	# Get plain diff
+	git diff -U1 >plain &&
+	cat >expected <<-EOF &&
+	diff --git a/x b/x
+	--- a/x
+	+++ b/x
+	@@ -1,4 +1,2 @@
+	-1
+	 2
+	-3
+	 4
+	EOF
+	compare_diff_patch expected plain &&
+
+	# Both removed lines match regex - ignore hunk
+	git diff -U1 -I "^[1-3]" >actual &&
+	test_must_be_empty actual &&
+
+	# First removed line does not match regex, but is out of context - ignore second change
+	git diff -U1 -I "^[2-3]" >actual &&
+	cat >second-change-ignored <<-EOF &&
+	diff --git a/x b/x
+	--- a/x
+	+++ b/x
+	@@ -1,2 +1 @@
+	-1
+	 2
+	EOF
+	compare_diff_patch second-change-ignored actual &&
+
+	# Second removed line does not match regex, but is out of context - ignore first change
+	git diff -U1 -I "^[1-2]" >actual &&
+	cat >first-change-ignored <<-EOF &&
+	diff --git a/x b/x
+	--- a/x
+	+++ b/x
+	@@ -2,3 +1,2 @@
+	 2
+	-3
+	 4
+	EOF
+	compare_diff_patch first-change-ignored actual
+'
+
+test_expect_success 'multiple hunks' '
+	test_seq 20 | sed "1d; 20d" >x &&
+
+	# Get plain diff
+	git diff >plain &&
+	cat >expected <<-EOF &&
+	diff --git a/x b/x
+	--- a/x
+	+++ b/x
+	@@ -1,4 +1,3 @@
+	-1
+	 2
+	 3
+	 4
+	@@ -17,4 +16,3 @@
+	 17
+	 18
+	 19
+	-20
+	EOF
+	compare_diff_patch expected plain &&
+
+	# Ignore both hunks
+	git diff -I "^[12]" >actual &&
+	test_must_be_empty actual &&
+
+	# Only ignore first hunk
+	git diff -I "^1" >actual &&
+	cat >first-hunk-ignored <<-EOF &&
+	diff --git a/x b/x
+	--- a/x
+	+++ b/x
+	@@ -17,4 +16,3 @@
+	 17
+	 18
+	 19
+	-20
+	EOF
+	compare_diff_patch first-hunk-ignored actual &&
+
+	# Only ignore second hunk
+	git diff -I "^2" >actual &&
+	cat >second-hunk-ignored <<-EOF &&
+	diff --git a/x b/x
+	--- a/x
+	+++ b/x
+	@@ -1,4 +1,3 @@
+	-1
+	 2
+	 3
+	 4
+	EOF
+	compare_diff_patch second-hunk-ignored actual
+'
+
+test_expect_success 'multiple hunks, with --ignore-blank-lines' '
+	echo >x &&
+	test_seq 21 >>x &&
+
+	# Get plain diff
+	git diff >plain &&
+	cat >expected <<-EOF &&
+	diff --git a/x b/x
+	--- a/x
+	+++ b/x
+	@@ -1,3 +1,4 @@
+	+
+	 1
+	 2
+	 3
+	@@ -18,3 +19,4 @@
+	 18
+	 19
+	 20
+	+21
+	EOF
+	compare_diff_patch expected plain &&
+
+	# -I does not override --ignore-blank-lines - ignore both hunks
+	git diff --ignore-blank-lines -I ^21 >actual &&
+	test_must_be_empty actual
+'
+
+test_expect_success 'diffstat' '
+	test_seq 20 | sed "s/^5/0/p; s/^15/10/; 16d" >x &&
+
+	# Get plain diffstat
+	git diff --stat >actual &&
+	cat >expected <<-EOF &&
+	 x | 6 +++---
+	 1 file changed, 3 insertions(+), 3 deletions(-)
+	EOF
+	test_cmp expected actual &&
+
+	# Ignore both hunks
+	git diff --stat -I "^[0-5]" >actual &&
+	test_must_be_empty actual &&
+
+	# Only ignore first hunk
+	git diff --stat -I "^[05]" >actual &&
+	cat >expected <<-EOF &&
+	 x | 3 +--
+	 1 file changed, 1 insertion(+), 2 deletions(-)
+	EOF
+	test_cmp expected actual &&
+
+	# Only ignore second hunk
+	git diff --stat -I "^1" >actual &&
+	cat >expected <<-EOF &&
+	 x | 3 ++-
+	 1 file changed, 2 insertions(+), 1 deletion(-)
+	EOF
+	test_cmp expected actual
+'
+
+test_expect_success 'invalid regex' '
+	>x &&
+	git diff -I "^[1" 2>&1 | grep "invalid regex: "
+'
+
+test_done
-- 
2.28.0