Add completions for bower

These are "true" completions, with dynamic completion of available
packages to be installed or removed.

CHANGELOG.md

@@ -61,6 +61,7 @@ This section is for changes merged to the `major` branch that are not also merge
 - Command substitution output is now limited to 10 MB by default (#3822).
 - Added completions for
   - `bd` (#4472)
+  - `bower`<sup>&#x2217;</sup>
   - `configure`
   - `j` (autojump #4344)
   - `jhipster` (#4472)
@@ -72,9 +73,10 @@ This section is for changes merged to the `major` branch that are not also merge
   - `git` (#4395, #4396, #4592)
   - `npm`<sup>†</sup>
   - `ssh` (#4344)
-  - `yarn`<sup>†</sup>
+  - `yarn`<sup>&#x2217;</sup><sup>†</sup>
 
-_† for autocompletion of available packages for installation via `npm` or `yarn`, make sure `all-the-package-names` is installed (typically: `sudo npm install -g all-the-package-names`)._
+&#x2217; _`jq` must be installed to complete the list of currently installed `bower` or `yarn` packages_. <br/>
+† _to autocomplete the list of packages available for installation with `npm` or `yarn`, `all-the-package-names` must be installed (typically: `sudo npm install -g all-the-package-names`)._
 
 --
 

share/completions/bower.fish

@@ -0,0 +1,63 @@
+function __bower_cmds
+	echo -en "cache\tManage bower cache
+help\tDisplay help information about Bower
+home\tOpens a package homepage into your favorite browser
+info\tInfo of a particular package
+init\tInteractively create a bower.json file
+install\tInstall a package locally
+link\tSymlink a package folder
+list\tList local packages - and possible updates
+login\tAuthenticate with GitHub and store credentials
+lookup\tLook up a single package URL by name
+prune\tRemoves local extraneous packages
+register\tRegister a package
+search\tSearch for packages by name
+update\tUpdate a local package
+uninstall\tRemove a local package
+unregister\tRemove a package from the registry
+version\tBump a package version
+"
+end
+
+function __bower_args
+	echo -en "-f\tMakes various commands more forceful
+--force\tMakes various commands more forceful
+-j\tOutput consumable JSON
+--json\tOutput consumable JSON
+-l\tWhat level of logs to report
+--loglevel\tWhat level of logs to report
+-o\tDo not hit the network
+--offline\tDo not hit the network
+-q\tOnly output important information
+--quiet\tOnly output important information
+-s\tDo not output anything, besides errors
+--silent\tDo not output anything, besides errors
+-V\tMakes output more verbose
+--verbose\tMakes output more verbose
+--allow-root\tAllows running commands as root
+-v\tOutput Bower version
+--version\tOutput Bower version
+--no-color\tDisable colors"
+end
+
+function __bower_matching_pkgs
+	bower search (commandline -ct) | string match -r "\S+[^\s]" | string match -v "Search"
+end
+
+# Output of `bower list` is a) slow, b) convoluted. Use `jq` instead.
+function __bower_list_installed
+	if not type -q jq
+		return 1
+	end
+
+	if not test -e bower.json
+		return 1
+	end
+
+	jq -r '.dependencies | to_entries[] | .key' bower.json
+end
+
+complete -c bower -n "__fish_is_first_token" -x -a '(__bower_cmds)'
+complete -c bower -n "__fish_should_complete_args" -x -a '(__bower_args)'
+complete -c bower -n "__fish_seen_subcommand_from install" -x -a '(__bower_matching_pkgs)'
+complete -c bower -n "__fish_seen_subcommand_from uninstall" -x -a '(__bower_list_installed)'