Merge branch 'jv/maint-no-ext-diff' into maint

"git diff --no-ext-diff" did not output anything for a typechange
filepair when GIT_EXTERNAL_DIFF is in effect.

* jv/maint-no-ext-diff:
diff: test precedence of external diff drivers
diff: correctly disable external_diff with --no-ext-diff

diff --git a/diff.c b/diff.c
index 208096fe461b483a0646bb583fd2158c3179823f..62cbe141efb411e831484fc36c0cba95a2b8846b 100644 (file)
--- a/diff.c
+++ b/diff.c
@@ -2992,9 +2992,8 @@ static void run_diff_cmd(const char *pgm,
        int complete_rewrite = (p->status == DIFF_STATUS_MODIFIED) && p->score;
        int must_show_header = 0;
 
-       if (!DIFF_OPT_TST(o, ALLOW_EXTERNAL))
-               pgm = NULL;
-       else {
+
+       if (DIFF_OPT_TST(o, ALLOW_EXTERNAL)) {
                struct userdiff_driver *drv = userdiff_find_by_path(attr_path);
                if (drv && drv->external)
                        pgm = drv->external;
@@ -3074,6 +3073,9 @@ static void run_diff(struct diff_filepair *p, struct diff_options *o)
        if (o->prefix_length)
                strip_prefix(o->prefix_length, &name, &other);
 
+       if (!DIFF_OPT_TST(o, ALLOW_EXTERNAL))
+               pgm = NULL;
+
        if (DIFF_PAIR_UNMERGED(p)) {
                run_diff_cmd(pgm, name, NULL, attr_path,
                             NULL, NULL, NULL, o, p);

diff --git a/t/t4020-diff-external.sh b/t/t4020-diff-external.sh
index 533afc1185114e8ea7e7e5e9315ceaf7816e32c2..2e7d73f0906e6a2808706236328470b2d855e9f9 100755 (executable)
--- a/t/t4020-diff-external.sh
+++ b/t/t4020-diff-external.sh
@@ -48,7 +48,53 @@ test_expect_success 'GIT_EXTERNAL_DIFF environment and --no-ext-diff' '
 
 '
 
+test_expect_success SYMLINKS 'typechange diff' '
+       rm -f file &&
+       ln -s elif file &&
+       GIT_EXTERNAL_DIFF=echo git diff  | {
+               read path oldfile oldhex oldmode newfile newhex newmode &&
+               test "z$path" = zfile &&
+               test "z$oldmode" = z100644 &&
+               test "z$newhex" = "z$_z40" &&
+               test "z$newmode" = z120000 &&
+               oh=$(git rev-parse --verify HEAD:file) &&
+               test "z$oh" = "z$oldhex"
+       } &&
+       GIT_EXTERNAL_DIFF=echo git diff --no-ext-diff >actual &&
+       git diff >expect &&
+       test_cmp expect actual
+'
+
+test_expect_success 'diff.external' '
+       git reset --hard &&
+       echo third >file &&
+       test_config diff.external echo &&
+       git diff | {
+               read path oldfile oldhex oldmode newfile newhex newmode &&
+               test "z$path" = zfile &&
+               test "z$oldmode" = z100644 &&
+               test "z$newhex" = "z$_z40" &&
+               test "z$newmode" = z100644 &&
+               oh=$(git rev-parse --verify HEAD:file) &&
+               test "z$oh" = "z$oldhex"
+       }
+'
+
+test_expect_success 'diff.external should apply only to diff' '
+       test_config diff.external echo &&
+       git log -p -1 HEAD |
+       grep "^diff --git a/file b/file"
+'
+
+test_expect_success 'diff.external and --no-ext-diff' '
+       test_config diff.external echo &&
+       git diff --no-ext-diff |
+       grep "^diff --git a/file b/file"
+'
+
 test_expect_success 'diff attribute' '
+       git reset --hard &&
+       echo third >file &&
 
        git config diff.parrot.command echo &&
 
@@ -113,6 +159,19 @@ test_expect_success 'diff attribute and --no-ext-diff' '
 
 '
 
+test_expect_success 'GIT_EXTERNAL_DIFF trumps diff.external' '
+       >.gitattributes &&
+       test_config diff.external "echo ext-global" &&
+       GIT_EXTERNAL_DIFF="echo ext-env" git diff | grep ext-env
+'
+
+test_expect_success 'attributes trump GIT_EXTERNAL_DIFF and diff.external' '
+       test_config diff.foo.command "echo ext-attribute" &&
+       test_config diff.external "echo ext-global" &&
+       echo "file diff=foo" >.gitattributes &&
+       GIT_EXTERNAL_DIFF="echo ext-env" git diff | grep ext-attribute
+'
+
 test_expect_success 'no diff with -diff' '
        echo >.gitattributes "file -diff" &&
        git diff | grep Binary