diff: fix the diffing of a concrete blob against a null one

diff --git a/src/diff_output.c b/src/diff_output.c
index 788c8b8f058a15ec7c5674c91aecd17951733648..dbcc89fa5e4de841865e3a8281795c4efd60735b 100644 (file)
--- a/src/diff_output.c
+++ b/src/diff_output.c
@@ -686,7 +686,6 @@ int git_diff_print_patch(
        return error;
 }
 
-
 int git_diff_blobs(
        git_blob *old_blob,
        git_blob *new_blob,
@@ -701,44 +700,43 @@ int git_diff_blobs(
        xpparam_t xdiff_params;
        xdemitconf_t xdiff_config;
        xdemitcb_t xdiff_callback;
+       git_blob *new, *old;
+
+       memset(&delta, 0, sizeof(delta));
+
+       new = new_blob;
+       old = old_blob;
 
        if (options && (options->flags & GIT_DIFF_REVERSE)) {
-               git_blob *swap = old_blob;
-               old_blob = new_blob;
-               new_blob = swap;
+               git_blob *swap = old;
+               old = new;
+               new = swap;
        }
 
-       if (old_blob) {
-               old_data.ptr  = (char *)git_blob_rawcontent(old_blob);
-               old_data.size = git_blob_rawsize(old_blob);
+       if (old) {
+               old_data.ptr  = (char *)git_blob_rawcontent(old);
+               old_data.size = git_blob_rawsize(old);
+               git_oid_cpy(&delta.old_file.oid, git_object_id((const git_object *)old));
        } else {
                old_data.ptr  = "";
                old_data.size = 0;
        }
 
-       if (new_blob) {
-               new_data.ptr  = (char *)git_blob_rawcontent(new_blob);
-               new_data.size = git_blob_rawsize(new_blob);
+       if (new) {
+               new_data.ptr  = (char *)git_blob_rawcontent(new);
+               new_data.size = git_blob_rawsize(new);
+               git_oid_cpy(&delta.new_file.oid, git_object_id((const git_object *)new));
        } else {
                new_data.ptr  = "";
                new_data.size = 0;
        }
 
        /* populate a "fake" delta record */
-       delta.status = old_data.ptr ?
-               (new_data.ptr ? GIT_DELTA_MODIFIED : GIT_DELTA_DELETED) :
-               (new_data.ptr ? GIT_DELTA_ADDED : GIT_DELTA_UNTRACKED);
-       delta.old_file.mode = 0000000; /* can't know the truth from a blob alone */
-       delta.new_file.mode = 0000000;
-       git_oid_cpy(&delta.old_file.oid, git_object_id((const git_object *)old_blob));
-       git_oid_cpy(&delta.new_file.oid, git_object_id((const git_object *)new_blob));
-       delta.old_file.path = NULL;
-       delta.new_file.path = NULL;
+       delta.status = new ?
+               (old ? GIT_DELTA_MODIFIED : GIT_DELTA_ADDED) :
+               (old ? GIT_DELTA_DELETED : GIT_DELTA_UNTRACKED);
        delta.old_file.size = old_data.size;
        delta.new_file.size = new_data.size;
-       delta.old_file.flags = 0;
-       delta.new_file.flags = 0;
-       delta.similarity = 0;
 
        info.diff    = NULL;
        info.delta   = δ

diff --git a/tests-clar/diff/blob.c b/tests-clar/diff/blob.c
index 65b350005158caca4543cb20c0723ad8f2346ccc..9364bdc6db580d3bba6a5161b5ed9e760d791b7d 100644 (file)
--- a/tests-clar/diff/blob.c
+++ b/tests-clar/diff/blob.c
@@ -2,23 +2,38 @@
 #include "diff_helpers.h"
 
 static git_repository *g_repo = NULL;
+static diff_expects exp;
+static git_diff_options opts;
+static git_blob *d;
 
 void test_diff_blob__initialize(void)
 {
+       git_oid d_oid;
+
        g_repo = cl_git_sandbox_init("attr");
+
+       memset(&opts, 0, sizeof(opts));
+       opts.context_lines = 1;
+       opts.interhunk_lines = 1;
+
+       memset(&exp, 0, sizeof(exp));
+
+       /* tests/resources/attr/root_test4.txt */
+       cl_git_pass(git_oid_fromstrn(&d_oid, "fe773770c5a6", 12));
+       cl_git_pass(git_blob_lookup_prefix(&d, g_repo, &d_oid, 6));
 }
 
 void test_diff_blob__cleanup(void)
 {
+       git_blob_free(d);
+
        cl_git_sandbox_cleanup();
 }
 
 void test_diff_blob__can_compare_text_blobs(void)
 {
-       git_blob *a, *b, *c, *d;
-       git_oid a_oid, b_oid, c_oid, d_oid;
-       git_diff_options opts = {0};
-       diff_expects exp;
+       git_blob *a, *b, *c;
+       git_oid a_oid, b_oid, c_oid;
 
        /* tests/resources/attr/root_test1 */
        cl_git_pass(git_oid_fromstrn(&a_oid, "45141a79", 8));
@@ -32,16 +47,8 @@ void test_diff_blob__can_compare_text_blobs(void)
        cl_git_pass(git_oid_fromstrn(&c_oid, "c96bbb2c2557a832", 16));
        cl_git_pass(git_blob_lookup_prefix(&c, g_repo, &c_oid, 8));
 
-       /* tests/resources/attr/root_test4.txt */
-       cl_git_pass(git_oid_fromstrn(&d_oid, "fe773770c5a6", 12));
-       cl_git_pass(git_blob_lookup_prefix(&d, g_repo, &d_oid, 6));
-
        /* Doing the equivalent of a `git diff -U1` on these files */
 
-       opts.context_lines = 1;
-       opts.interhunk_lines = 1;
-
-       memset(&exp, 0, sizeof(exp));
        cl_git_pass(git_diff_blobs(
                a, b, &opts, &exp, diff_hunk_fn, diff_line_fn));
 
@@ -86,6 +93,28 @@ void test_diff_blob__can_compare_text_blobs(void)
        git_blob_free(a);
        git_blob_free(b);
        git_blob_free(c);
-       git_blob_free(d);
 }
 
+void test_diff_blob__can_compare_against_null_blobs(void)
+{
+       git_blob *e = NULL;
+
+       cl_git_pass(git_diff_blobs(
+               d, e, &opts, &exp, diff_hunk_fn, diff_line_fn));
+
+       cl_assert(exp.hunks == 1);
+       cl_assert(exp.hunk_old_lines == 14);
+       cl_assert(exp.lines == 14);
+       cl_assert(exp.line_dels == 14);
+
+       opts.flags |= GIT_DIFF_REVERSE;
+       memset(&exp, 0, sizeof(exp));
+
+       cl_git_pass(git_diff_blobs(
+               d, e, &opts, &exp, diff_hunk_fn, diff_line_fn));
+
+       cl_assert(exp.hunks == 1);
+       cl_assert(exp.hunk_new_lines == 14);
+       cl_assert(exp.lines == 14);
+       cl_assert(exp.line_adds == 14);
+}