add chinese for pages.cn/linux/add-apt-respository.md

pages.cn/common/git-diff.md

@@ -0,0 +1,39 @@
+# git diff
+
+> Show changes to tracked files.
+
+- Show unstaged, uncommitted changes:
+
+`git diff`
+
+- Show all uncommitted changes (including staged ones):
+
+`git diff HEAD`
+
+- Show only staged (added, but not yet committed) changes:
+
+`git diff --staged`
+
+- Show changes from all commits since a given date/time (a date expression, e.g. "1 week 2 days" or an ISO date):
+
+`git diff 'HEAD@{3 months|weeks|days|hours|seconds ago}'`
+
+- Show only names of changed files since a given commit:
+
+`git diff --name-only {{commit}}`
+
+- Output a summary of file creations, renames and mode changes since a given commit:
+
+`git diff --summary {{commit}}`
+
+- Create a patch file:
+
+`git diff > {{target_file}}.patch`
+
+- Compare a single file between two branches or commits:
+
+`git diff {{branch_1}}..{{branch_2}} [--] {{path/to/file}}`
+
+- Compare different files from the current branch to other branch:
+
+`git diff {{branch}}:{{path/to/file2}} {{path/to/file}}`