Configuring Git
The properties and behaviour of Git can be customized using special files within your repo. These can control which files Git tracks as well as give certain properties to certain files within a Git repo.
.gitignore
The .gitignore file is used to specify files or file patterns you wish for Git to ignore. File patterns are specified using Unix-based globbing (ie. the use of wildcard patterns).
.gitattributes
The .gitattributes file is used to specify the attributes of files or file patterns. One particular useful case of the .gitattributes file is to ensure the correct End-of-Line (EOL) characters are used in certain files as the default choice between Unix-like systems and Windows is different which can lead to some unique bugs and inconsistencies when collaborating with people using different systems. It also allows you to control exactly which files these attributes apply to ensuring only the right files are affected.
| Pattern | Examples | Explanation |
|---|---|---|
**/logs | logs/debug.log logs/monday/foo.bar build/logs/debug.log | You can prepend a pattern with a double asterisk to match directories anywhere in the repository. |
**/logs/debug.log | logs/debug.log build/logs/debug.log but not logs/build/debug.log | You can also use a double asterisk to match files based on their name and the name of their parent directory. |
*.log | debug.log foo.log .log logs/debug.log | An asterisk is a wildcard that matches zero or more characters. |
*.log !important.log | debug.log trace.log but not important.log logs/important.log | Prepending an exclamation mark to a pattern negates it. If a file matches a pattern, but also matches a negating pattern defined later in the file, it will not be ignored. |
*.log !important/*.log trace.* | debug.log important/trace.log but not important/debug.log | Patterns defined after a negating pattern will re-ignore any previously negated files. |
/debug.log | debug.log but not logs/debug.log | Prepending a slash matches files only in the repository root. |
debug.log | debug.log logs/debug.log | By default, patterns match files in any directory |
debug?.log | debug0.log debugg.log but not debug10.log | A question mark matches exactly one character. |
debug[0-9].log | debug0.log debug1.log but not debug10.log | Square brackets can also be used to match a single character from a specified range. |
debug[01].log | debug0.log debug1.log but not debug2.log debug01.log | Square brackets match a single character form the specified set. |
debug[!01].log | debug2.log but not debug0.log debug1.log debug01.log | An exclamation mark can be used to match any character except one from the specified set. |
debug[a-z].log | debuga.log debugb.log but not debug1.log | Ranges can be numeric or alphabetic. |
logs | logs logs/debug.log logs/latest/foo.bar build/logs build/logs/debug.log | If you don't append a slash, the pattern will match both files and the contents of directories with that name. In the example matches on the left, both directories and files named logs are ignored |
logs/ | logs/debug.log logs/latest/foo.bar build/logs/foo.bar build/logs/latest/debug.log | Appending a slash indicates the pattern is a directory. The entire contents of any directory in the repository matching that name – including all of its files and subdirectories – will be ignored |
logs/ !logs/important.log | logs/debug.log logs/important.log | Wait a minute! Shouldn't logs/important.log be negated in the example on the left Nope! Due to a performance-related quirk in Git, you can not negate a file that is ignored due to a pattern matching a directory |
logs/**/debug.log | logs/debug.log logs/monday/debug.log logs/monday/pm/debug.log | A double asterisk matches zero or more directories. |
logs/*day/debug.log | logs/monday/debug.log logs/tuesday/debug.log but not logs/latest/debug.log | Wildcards can be used in directory names as well. |
| logs/debug.log | logs/debug.log but not debug.log build/logs/debug.log | Patterns specifying a file in a particular directory are relative to the repository root. (You can prepend a slash if you like, but it doesn't do anything special.) |
Note:
- These explanations assume your
.gitignorefile is in the top level directory of your repository, as is the convention. If your repository has multiple.gitignorefiles, simply mentally replace "repository root" with "directory containing the.gitignorefile" (and consider unifying them, for the sanity of your team).- Additionally, lines starting
#are treated as comments and a\character can be prepended to a character that usually has a special meaning to escape it (ie. match the literal character[(using\[in the.gitignore) that is in a file name instead of start a match group).
Example .gitattributes
# Use the 'line feed' EOL character for all files
* eol=lf
# Use the 'carriage return & line feed' EOL character for text files
*.txt eol=crlf