How to search the git log

What is git log --grep?

The git log command displays the commit history of the current branch. By adding the --grep option, you can filter this log to show only those commits whose commit message contains a certain string or matches a regex pattern.

This guide explains how to use git log --grep effectively, including searching commit messages, the entire project history, and across all branches.

Using git log --grep to filter commit messages

1. Basic string search: To find commits with a specific string in their commit message, you can use:

   Terminal

   git log --grep="Fix bug"
   
   

   This command displays all commits where the commit message contains "Fix bug".

2. Regular expression search: If you're looking for commits with messages that match a more complex pattern, you can use regular expressions (regex):

   Terminal

   git log --grep="JIRA-[0-9]+"
   
   

   This regex pattern matches commit messages that refer to a JIRA ticket, such as "JIRA-1234".

   For combining patterns that should match any of the specified conditions (OR logic), you can use regular expressions within a single --grep option:

   Terminal

   git log --grep="\(UI\|bug\)"
   
   

   This uses the regular expression \(UI\|bug\) to find commits whose messages contain either "UI" or "bug".

Advanced search techniques

1. Case-insensitive search: Add the -i option to perform a case-insensitive search:

   Terminal

   git log --grep="fix bug" -i
   
   

2. Combining multiple --grep conditions If you need to find commits that must meet multiple criteria (AND logic), you can specify multiple --grep options. This will work because git log implicitly uses AND logic when multiple --grep flags are used:

   Terminal

   git log --grep="UI" --grep="bug"
   
   

   This command will return commits that contain both "UI" and "bug" in their messages, as git log treats multiple --grep conditions as needing to all be true.

3. Searching across all branches: To extend the search across all branches, include the --all flag:

   Terminal

   git log --all --grep="UI update"
   
   

4. Searching for strings in files: If you want to search the history for a specific string within the files (not just the commit messages), use git grep in combination with git log:

   Terminal

   git grep "functionName" $(git rev-list --all)
   
   

   This command searches for "functionName" in all files across the entire history of the repository.

For further reading on searching the log with grep see the official Git documentation.