Re: [PATCH v2 6/6] fsmonitor: add a sample query-fsmonitor hook script for Watchman
From: Christian Couder <hidden>
Date: 2017-05-24 13:13:00
On Thu, May 18, 2017 at 10:13 PM, Ben Peart [off-list ref] wrote:
This hook script integrates the new fsmonitor capabilities of git with the cross platform Watchman file watching service. To use the script: Download and install Watchman from https://facebook.github.io/watchman/ and instruct Watchman to watch your working directory for changes ('watchman watch-project /usr/src/git'). Rename the sample integration hook from query-fsmonitor.sample to query-fsmonitor. Configure git to use the extension ('git config core.fsmonitor true') and optionally turn on the untracked cache for optimal performance ('git config core.untrackedcache true').
Ok, it looks like the untracked cache can be used, but it could work without it.
quoted hunk ↗ jump to hunk
Signed-off-by: Ben Peart <redacted> Signed-off-by: Johannes Schindelin <redacted> --- templates/hooks--query-fsmonitor.sample | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) create mode 100644 templates/hooks--query-fsmonitor.samplediff --git a/templates/hooks--query-fsmonitor.sample b/templates/hooks--query-fsmonitor.sample new file mode 100644 index 0000000000..4bd22f21d8 --- /dev/null +++ b/templates/hooks--query-fsmonitor.sample@@ -0,0 +1,27 @@ +#!/bin/sh +# +# An example hook script to integrate Watchman +# (https://facebook.github.io/watchman/) with git to provide fast +# git status. +# +# The hook is passed a time_t formatted as a string and outputs to +# stdout all files that have been modified since the given time. +# Paths must be relative to the root of the working tree and +# separated by a single NUL. +# +# To enable this hook, rename this file to "query-fsmonitor" + +# Convert unix style paths to escaped Windows style paths +case "$(uname -s)" in +MINGW*|MSYS_NT*) + GIT_WORK_TREE="$(cygpath -aw "$PWD" | sed 's,\\,\\\\,g')" + ;; +*) + GIT_WORK_TREE="$PWD" + ;; +esac + +# Query Watchman for all the changes since the requested time +echo "[\"query\", \"$GIT_WORK_TREE\", {\"since\": $1, \"fields\":[\"name\"]}]" | \ +watchman -j | \ +perl -e 'use JSON::PP; my $o = JSON::PP->new->utf8->decode(join("", <>)); die "Watchman: $o->{'error'}.\nFalling back to scanning...\n" if defined($o->{"error"}); print(join("\0", @{$o->{"files"}}));'
Maybe put the above small perl script on multiple lines for improved readability. Is JSON::PP always available in Perl >= 5.8? What happens if watchman is not installed or not in the PATH? It seems to me that the git process will not die, and will just work as if the hook does not exist, except that it will call the hook which will probably output error messages.