lsp: Use nvim_buf_get_lines in locations_to_items and add more tests (#12357)

* LSP: Add tests & use nvim_buf_get_lines in locations_to_items

This is to add support for cases where the server returns a URI in the
locations that does not have a file scheme but needs to be loaded via a
BufReadCmd event.

* LSP: Don't iterate through all lines in locations_to_items

* fixup! LSP: Don't iterate through all lines in locations_to_items

* fixup! fixup! LSP: Don't iterate through all lines in locations_to_items

* fixup! fixup! fixup! LSP: Don't iterate through all lines in locations_to_items

1 files changed, 58 insertions, 0 deletions

diff --git a/test/functional/plugin/lsp_spec.lua b/test/functional/plugin/lsp_spec.lua
index 4b12ea2557..1b022f50df 100644
--- a/test/functional/plugin/lsp_spec.lua
+++ b/test/functional/plugin/lsp_spec.lua
@@ -1070,6 +1070,64 @@ describe('LSP', function()
       ]])
     end)
   end)
+  describe('lsp.util.locations_to_items', function()
+    it('Convert Location[] to items', function()
+      local expected = {
+        {
+          filename = 'fake/uri',
+          lnum = 1,
+          col = 3,
+          text = 'testing'
+        },
+      }
+      local actual = exec_lua [[
+        local bufnr = vim.uri_to_bufnr("file://fake/uri")
+        local lines = {"testing", "123"}
+        vim.api.nvim_buf_set_lines(bufnr, 0, 1, false, lines)
+        local locations = {
+          {
+            uri = 'file://fake/uri',
+            range = {
+              start = { line = 0, character = 2 },
+              ['end'] = { line = 0, character = 3 },
+            }
+          },
+        }
+        return vim.lsp.util.locations_to_items(locations)
+      ]]
+      eq(expected, actual)
+    end)
+    it('Convert LocationLink[] to items', function()
+      local expected = {
+        {
+          filename = 'fake/uri',
+          lnum = 1,
+          col = 3,
+          text = 'testing'
+        },
+      }
+      local actual = exec_lua [[
+        local bufnr = vim.uri_to_bufnr("file://fake/uri")
+        local lines = {"testing", "123"}
+        vim.api.nvim_buf_set_lines(bufnr, 0, 1, false, lines)
+        local locations = {
+          {
+            targetUri = vim.uri_from_bufnr(bufnr),
+            targetRange = {
+              start = { line = 0, character = 2 },
+              ['end'] = { line = 0, character = 3 },
+            },
+            targetSelectionRange = {
+              start = { line = 0, character = 2 },
+              ['end'] = { line = 0, character = 3 },
+            }
+          },
+        }
+        return vim.lsp.util.locations_to_items(locations)
+      ]]
+      eq(expected, actual)
+    end)
+  end)
   describe('lsp.util.symbols_to_items', function()
     describe('convert DocumentSymbol[] to items', function()
       it('DocumentSymbol has children', function()