20150921: Zsh 5.1 and bracketed paste

1 files changed, 52 insertions, 0 deletions

diff --git a/source/blog/2015-09-21-zsh-51-and-bracketed-paste.md b/source/blog/2015-09-21-zsh-51-and-bracketed-paste.md
new file mode 100644
index 00000000..3750f566
--- /dev/null
+++ b/source/blog/2015-09-21-zsh-51-and-bracketed-paste.md
@@ -0,0 +1,52 @@
+---
+title: "Zsh 5.1 and bracketed paste"
+date: 2015-09-21T14:40:36-07:00
+date-display: September 21, 2015
+---
+**TL;DR.** Jump to [code](#code).
+
+---
+
+In short, Zsh 5.1 introduced bracketed paste mode[^1] and turned it on by default (as it seems to me). It is nice in certain ways — I appreciate the change, yet I was bitten nevertheless. In at least two ways:
+
+1. Most annoyingly, `url-quote-magic` doesn't work anymore when pasting URLs, so for example if I paste
+
+        https://www.google.com/search?q=zsh
+
+    without typing in a single or double quote first, the `?` won't be backslash-quoted by default, which causes a syntax error when passed unnoticed (out of habit).
+
+2. The Emacs shell[^2] is littered with `^[[?2004h` and `^[[?2004l` around every prompt.
+
+The solution? Zsh now also ships with [`bracketed-paste-magic`](https://github.com/zsh-users/zsh/blob/master/Functions/Zle/bracketed-paste-magic) that solves exactly breakage #1 (and a bit more); to quote comments from the linked source file:
+
+> Starting with zsh-5.1, ZLE began to recognize the "bracketed paste"
+capability of terminal emulators, that is, the sequences `$'\e[200~'` to
+start a paste and `$'\e[201~'` to indicate the end of the pasted text.
+Pastes are handled by the bracketed-paste widget and insert literally
+into the editor buffer rather than being interpreted as keystrokes.
+>
+> This disables some common usages where the self-insert widget has been
+replaced in order to accomplish some extra processing.  An example is
+the contributed url-quote-magic widget.  The bracketed-paste-magic
+widget replaces bracketed-paste with a wrapper that re-enables these
+self-insert actions, and other actions as selected by the zstyles
+described below.
+
+And to solve breakage #2, just disable bracketed paste altogether for dumb terms.
+
+<p id="code">Putting it together:</p>
+
+```zsh
+# turn off ZLE bracketed paste in dumb term
+# otherwise turn on ZLE bracketed-paste-magic
+if [[ $TERM == dumb ]]; then
+    unset zle_bracketed_paste
+else
+    autoload -Uz bracketed-paste-magic
+    zle -N bracketed-paste bracketed-paste-magic
+fi
+```
+
+[^1]: Bracketed paste mode is a safeguard against inadvertent interpretation of pasted text, e.g., newline being treated at `accept-line` in Zsh. You may read more about it [in this blog post](https://cirw.in/blog/bracketed-paste), which is somewhat outdated yet still informational.
+
+[^2]: I seldom use this dumb (literally) thing, but when I do I expect it to work ungarbled, naturally.