Commit 966b944095edf9910a332bb73249b5d7d6ebeb2f

Patrick Steinhardt 2019-02-21T08:30:22

tests: apply: verify that we correctly truncate the source buffer Previously, we would fail to correctly truncate the source buffer if the source has more than one line and ends with a non-newline character. In the following call, we thus truncate the source string in the middle of the second line. Without the bug fixed, we would successfully apply the patch to the source and return success. With the overflow being fixed, we should return an error now.

diff --git a/tests/apply/fromdiff.c b/tests/apply/fromdiff.c
index 8a6d8fa..832415d 100644
--- a/tests/apply/fromdiff.c
+++ b/tests/apply/fromdiff.c
@@ -333,3 +333,36 @@ void test_apply_fromdiff__binary_delete(void)
 		NULL, NULL,
 		NULL, &binary_opts));
 }
+
+void test_apply_fromdiff__patching_correctly_truncates_source(void)
+{
+	git_buf original = GIT_BUF_INIT, patched = GIT_BUF_INIT;
+	git_patch *patch;
+	unsigned int mode;
+	char *path;
+
+	cl_git_pass(git_patch_from_buffers(&patch,
+					   "foo\nbar", 7, "file.txt",
+					   "foo\nfoo", 7, "file.txt", NULL));
+
+	/*
+	 * Previously, we would fail to correctly truncate the source buffer if
+	 * the source has more than one line and ends with a non-newline
+	 * character. In the following call, we thus truncate the source string
+	 * in the middle of the second line. Without the bug fixed, we would
+	 * successfully apply the patch to the source and return success. With
+	 * the overflow being fixed, we should return an error.
+	 */
+	cl_git_fail_with(GIT_EAPPLYFAIL,
+			 git_apply__patch(&patched, &path, &mode,
+					  "foo\nbar\n", 5, patch, NULL));
+
+	/* Verify that the patch succeeds if we do not truncate */
+	cl_git_pass(git_apply__patch(&patched, &path, &mode,
+				     "foo\nbar\n", 7, patch, NULL));
+
+	git_buf_dispose(&original);
+	git_buf_dispose(&patched);
+	git_patch_free(patch);
+	git__free(path);
+}