From 9f3fd5449d02d84c21ae7cfbffa0246ad38a2136 Mon Sep 17 00:00:00 2001
From: Danielle McLean <dani@00dani.me>
Date: Tue, 24 Oct 2023 15:01:43 +1100
Subject: [PATCH] Add Perl::LanguageServer to config

---
 dot-config/vim/lsp.vim        | 12 ++++++++++--
 dot-config/vim/tools/perl.vim | 27 +++++++++++++++++++++++++++
 2 files changed, 37 insertions(+), 2 deletions(-)
 create mode 100644 dot-config/vim/tools/perl.vim

diff --git a/dot-config/vim/lsp.vim b/dot-config/vim/lsp.vim
index 9a1c804..1afca4c 100644
--- a/dot-config/vim/lsp.vim
+++ b/dot-config/vim/lsp.vim
@@ -1,5 +1,7 @@
 vim9script
 
+import './tools/perl.vim'
+
 const lspServers = [
 	{
 		name: 'dockerfile-langserver',
@@ -25,6 +27,8 @@ const lspServers = [
 		install: 'npm install -g perlnavigator-server',
 	},
 
+	perl.Lsp('Perl::LanguageServer', ['-e', 'Perl::LanguageServer::run']),
+
 	{
 		name: 'taplo',
 		filetype: 'toml',
@@ -128,12 +132,16 @@ def ToStringSet(stringList: list<string>): dict<bool>
 	return stringSet
 enddef
 
+def IsInstalled(server: dict<any>): bool
+	return server->has_key('installed') ? server.installed() : executable(server.path) == 1
+enddef
+
 def InstalledServers(): list<dict<any>>
-	return lspServers->deepcopy()->filter((_, server): bool => executable(server.path) == 1)
+	return lspServers->deepcopy()->filter((_, server): bool => server->IsInstalled())
 enddef
 
 def MissingServers(): list<dict<any>>
-	return lspServers->deepcopy()->filter((_, server): bool => executable(server.path) == 0)
+	return lspServers->deepcopy()->filter((_, server): bool => !server->isInstalled())
 enddef
 
 def ListMissingServers(argLead: string, cmdLine: string, cursorPos: number): list<string>
diff --git a/dot-config/vim/tools/perl.vim b/dot-config/vim/tools/perl.vim
new file mode 100644
index 0000000..17ae67d
--- /dev/null
+++ b/dot-config/vim/tools/perl.vim
@@ -0,0 +1,27 @@
+vim9script
+
+export def Lsp(module: string, args: list<string>): dict<any>
+	const lsp = {
+		name: module,
+		filetype: 'perl',
+		path: exepath('perl'),
+		args: [$'-M{module}']->extend(args),
+		install: $'cpanm {module}',
+		installed: (): bool => HasModule(module),
+	}
+	return lsp
+enddef
+
+export def HasModule(module: string): bool
+	# This can more reliably be tested by calling `perl -MModule::Name -E ''`
+	# and checking the exit status, but simply looking for a matching file on
+	# disk is much faster and works fine for my purposes.
+	const libs = $PERL5LIB->split(';')
+	const filename = module->substitute('::', '/', 'g') .. '.pm'
+	for lib in libs
+		if filereadable($'{lib}/{filename}')
+			return true
+		endif
+	endfor
+	return false
+enddef