Merge pull request #599 from atticus-sullivan/hotfix_nil_in_get_snippets

Hotfix nil in get snippets + adds test for error
Closes #591

Author: L3MON4D3

doc/luasnip.txt

@@ -1,4 +1,4 @@
-*luasnip.txt*          For NVIM v0.5.0          Last change: 2022 September 14
+*luasnip.txt*          For NVIM v0.5.0          Last change: 2022 September 15
 
 ==============================================================================
 Table of Contents                                  *luasnip-table-of-contents*

lua/luasnip/session/snippet_collection.lua

@@ -217,6 +217,7 @@ function M.clean_invalidated(opts)
 
 	for type, type_snippets in pairs(by_ft) do
 		by_ft[type] = without_invalidated(type_snippets)
+		setmetatable(by_ft[type], by_ft_snippets_mt)
 	end
 
 	for key, key_snippets in pairs(by_key) do

tests/unit/snippet_collection_spec.lua

@@ -46,3 +46,25 @@ describe("snippet_collection.add/get", function()
 		assert.is_true(foo())
 	end)
 end)
+
+describe("add_snippets invalidation", function()
+	-- apparently clear() needs to run before anything else...
+	helpers.clear()
+	helpers.exec("set rtp+=" .. os.getenv("LUASNIP_SOURCE"))
+
+	it("", function()
+		local function foo()
+			return helpers.exec_lua([[
+					local s,t = require("luasnip").snippet, require("luasnip").text_node
+					local collection = require("luasnip.session.snippet_collection")
+					collection.clear_snippets()
+					local s1,s2 = s("trig1", t("snippet1")), s("trig2", t("snippet2"))
+					local opts = {type="snippets", default_priority=1000, key="abc"}
+					collection.add_snippets({["txt"]={s1,s2}}, opts)
+					collection.clean_invalidated({ inv_limit = -1 })
+					local r = collection.get_snippets("nonExistantFT", "snippets")
+					]])
+		end
+		assert.has_no.errors(foo)
+	end)
+end)