replace

Generic file search & replace tool, written in Python.

Options

Specify the FROM/TO patterns directly in the command line:

-f, --from TEXT         specify the search text or regex
-t, --to TEXT           specify the replacement text

Specify the FROM/TO patterns using files, useful for multiline matches:

-F, --from-file FILE    read the search text from this file
-T, --to-file FILE      read the replacement text from this file

The default search uses simple string matching, no magic. But if you need power, there you have it:

-r, --regex             use regex matching instead of string matching

Just like sed, this script by default show results to STDOUT. But instead, you can save the edits to the original file:

-i, --in-place          edit files in-place

Examples

# Replace all mentions of old.css with new.css in all HTML files
replace --from old.css --to new.css --in-place *.html

# Update the AdSense code in all HTML files
# The old and the new code are in separate files
replace --from-file adsense.old --to-file adsense.new -i *.html

# Enclose all numbers inside square brackets: 123 -> [123]
replace --regex --from '(\d+)' --to '[\\1]' file.txt

# From http to https in all HTML files, recursive
find . -type f -name "*.html" \
    -exec replace \
      -f 'http://example.com' \
      -t 'https://example.com' \
      -i {} \;

Tests

The following command lines are executed and verified by clitest, using the clitest README.md command.

First, setup a sample text file:

$ echo 'the quick brown fox' > file.txt
$ cat file.txt
the quick brown fox
$

Now we'll do some replaces using string matching, which is the default. Note that there are short and long options (-f/--from) and that the replacement is performed globally: all occurrences are replaced.

$ ./replace.py --from 'brown' --to 'red' file.txt
the quick red fox
$ ./replace.py -f 'brown' -t 'red' file.txt
the quick red fox
$ ./replace.py -f 'o' -t '◆' file.txt
the quick br◆wn f◆x
$

For more powerfull searches, use -r or --regex to perform a regular expression match. You have access to the full power of Python's regex flavor.

$ ./replace.py --regex -f '[aeiou]' -t '◆' file.txt
th◆ q◆◆ck br◆wn f◆x
$ ./replace.py -r -f '[aeiou]' -t '◆' file.txt
th◆ q◆◆ck br◆wn f◆x
$

If necessary, you can also apply the replacements on text coming from STDIN, using - as the file name.

$ cat file.txt | ./replace.py -r -f '[aeiou]' -t '◆' -
th◆ q◆◆ck br◆wn f◆x
$

Note that all the previous replaces were not saved to the original file. This is the default behavior (just like sed). If you want to edit the original file, use the -i or --in-place options:

$ ./replace.py -r -f '[aeiou]' -t '◆' -i file.txt
Saved file.txt
$ cat file.txt
th◆ q◆◆ck br◆wn f◆x
$

Some boring tests for missing or incomplete command line options:

$ ./replace.py 2>&1 | grep error
replace.py: error: the following arguments are required: FILE
$ ./replace.py README.md
Error: No search pattern (use --from or --from-file)
$ ./replace.py -f '' README.md
Error: No search pattern (use --from or --from-file)
$ ./replace.py -f foo README.md
Error: No replace pattern (use --to or --to-file)
$

OK, we're done for now.

$ rm file.txt
$

Similar tools

• https://github.com/dmerejkowsky/replacer/
• https://github.com/facebook/codemod