t7810: improve check of -W with user-defined function lines

The check for function context (-W) together with user-defined function
line patterns reuses hello.c and pretends it's written in a language in
which function lines contain either "printf" or a trailing curly brace.
That's a bit obscure.

Make the test easier to read by adding a small PowerShell script, using
a simple, but meaningful expression, and separating out checks for
different aspects into dedicated tests instead of simply matching the
whole output byte for byte.

Also include a test for showing comments before function lines like git

Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/t/t7810-grep.sh b/t/t7810-grep.sh
index 2a6679c2f596fb13a34786a4aa4b954e61c61113..632b905611a1b818067d0493d95d67b712988fdd 100755 (executable)
--- a/t/t7810-grep.sh
+++ b/t/t7810-grep.sh
@@ -60,6 +60,18 @@ test_expect_success setup '
                echo " line with leading space3"
                echo "line without leading space2"
        } >space &&
+       cat >hello.ps1 <<-\EOF &&
+       # No-op.
+       function dummy() {}
+
+       # Say hello.
+       function hello() {
+         echo "Hello world."
+       } # hello
+
+       # Still a no-op.
+       function dummy() {}
+       EOF
        git add . &&
        test_tick &&
        git commit -m initial
@@ -766,18 +778,27 @@ test_expect_success 'grep -W shows no trailing empty lines' '
        test_cmp expected actual
 '
 
-cat >expected <<EOF
-hello.c=       printf("Hello world.\n");
-hello.c:       return 0;
-hello.c-       /* char ?? */
-EOF
-
 test_expect_success 'grep -W with userdiff' '
        test_when_finished "rm -f .gitattributes" &&
-       git config diff.custom.xfuncname "(printf.*|})$" &&
-       echo "hello.c diff=custom" >.gitattributes &&
-       git grep -W return >actual &&
-       test_cmp expected actual
+       git config diff.custom.xfuncname "^function .*$" &&
+       echo "hello.ps1 diff=custom" >.gitattributes &&
+       git grep -W echo >function-context-userdiff-actual
+'
+
+test_expect_failure ' includes preceding comment' '
+       grep "# Say hello" function-context-userdiff-actual
+'
+
+test_expect_success ' includes function line' '
+       grep "=function hello" function-context-userdiff-actual
+'
+
+test_expect_success ' includes matching line' '
+       grep ":  echo" function-context-userdiff-actual
+'
+
+test_expect_success ' includes last line of the function' '
+       grep "} # hello" function-context-userdiff-actual
 '
 
 for threads in $(test_seq 0 10)