Emacs: Find Replace Text in Directory

Suppose you want to do find and replace, for hundreds of files in a directory, either in one shot, or asking yes/no for each occurrence. Here's the solution.

Note: you need to have unix commands grep find xargs installed. If not, you can use Emacs: Find Replace in Pure Elisp, xah-find.el

Select Target Directory

Alt+x dired, then type a directory path, to list a directory.

Press ^ to go up a directory.

Now, your cursor should be on the directory you want to do the find/replace.

Select Only Some Files

If you want to find/replace only files ending in “.html”, or “.js”, or other selections of files, you need to mark files.

• When there are marked files, emacs will do find/replace only on those marked ones.
• When there are no marked files, emacs will do find/replace on the file/directory the cursor is on.

Mark Files/Directories

m

Mark the file/directory under cursor.

u

Unmark the file/directory under cursor.

U

Unmark all marked.

Mark Files by Regex

Alt+x dired-mark-files-regexp 【% m】

then type your regex pattern.

For example, if you want to mark all files ending in “.html”, then type % m then \.html$.

[see Emacs: Regex Tutorial]

Interactive Find Replace

Alt+x dired-do-query-replace-regexp 【Q】.

Answer the prompt, by typing find regex string and replace string.

For example, type “queen” Enter then “princess”, to replace words “queen” by “princess”.

[see Emacs: Regex Tutorial]

The Result Window

Emacs will show result, in a split window.

The top pane, is a file where a match is found. Cursor is place on the word.

The bottom pane shows a list of files where match is found. This buffer is name “*xref*”.

In the top pane showing the actual file, the following keys are available:

y

Replace current highlighted occurrence. (emacs will then jump to next one.)

n

Skip.

Ctrl+g

Abort the whole find/replace.

!

Replace all occurrences in current file without more asking.

N

Skip all possible replacement for rest of the current file.

Y

Do the replacement on all files without further asking.

If you want to cancel the whole operation without saving any changes you've made, type Ctrl+g, then exit emacs.

Result Overview: xref buffer

The bottom pane buffer named “*xref*”, lists all the occurrences and files.

Move cursor to the “*xref*” pane, then the following keys are available:

Enter

Display the reference on the current line.

n or .

Move to the next reference and display it in the other window (xref-next-line).

p or ,

Move to the previous reference and display it in the other window (xref-prev-line).

Ctrl+o

Display the reference on the current line in the other window (xref-show-location-at-point).

r

Prompt for find replace with regex. (xref-query-replace-in-results)

q

Quit the window showing the *xref* buffer. (quit-window)

In the xref buffer, Alt+x describe-mode to see the doc.

(info "(emacs) Xref Commands")

Save Changed Files

Alt+x ibuffer to list all opened files.

1. Type * u to mark all unsaved files
2. type S to save all marked files
3. type D to close them all.

Alternative to the above options, Alt+x save-some-buffers 【Ctrl+x s】. Then emacs will display each unsaved file and ask if you want it saved.