fix(lsp): correctly parse LSP snippets #15579

Fixes #15522

1 files changed, 152 insertions, 0 deletions

diff --git a/test/functional/plugin/lsp/snippet_spec.lua b/test/functional/plugin/lsp/snippet_spec.lua
new file mode 100644
index 0000000000..4e127743eb
--- /dev/null
+++ b/test/functional/plugin/lsp/snippet_spec.lua
@@ -0,0 +1,152 @@
+local helpers = require('test.functional.helpers')(after_each)
+local snippet = require('vim.lsp._snippet')
+
+local eq = helpers.eq
+local exec_lua = helpers.exec_lua
+
+describe('vim.lsp._snippet', function()
+  before_each(helpers.clear)
+  after_each(helpers.clear)
+
+  local parse = function(...)
+    return exec_lua('return require("vim.lsp._snippet").parse(...)', ...)
+  end
+
+  it('should parse only text', function()
+    eq({
+      type = snippet.NodeType.SNIPPET,
+      children = {
+        {
+          type = snippet.NodeType.TEXT,
+          raw = 'TE\\$\\}XT',
+          esc = 'TE$}XT'
+        }
+      }
+    }, parse('TE\\$\\}XT'))
+  end)
+
+  it('should parse tabstop', function()
+    eq({
+      type = snippet.NodeType.SNIPPET,
+      children = {
+        {
+          type = snippet.NodeType.TABSTOP,
+          tabstop = 1,
+        },
+        {
+          type = snippet.NodeType.TABSTOP,
+          tabstop = 2,
+        }
+      }
+    }, parse('$1${2}'))
+  end)
+
+  it('should parse placeholders', function()
+    eq({
+      type = snippet.NodeType.SNIPPET,
+      children = {
+        {
+          type = snippet.NodeType.PLACEHOLDER,
+          tabstop = 1,
+          children = {
+            {
+              type = snippet.NodeType.PLACEHOLDER,
+              tabstop = 2,
+              children = {
+                {
+                  type = snippet.NodeType.TEXT,
+                  raw = 'TE\\$\\}XT',
+                  esc = 'TE$}XT'
+                },
+                {
+                  type = snippet.NodeType.TABSTOP,
+                  tabstop = 3,
+                },
+                {
+                  type = snippet.NodeType.TABSTOP,
+                  tabstop = 1,
+                  transform = {
+                    type = snippet.NodeType.TRANSFORM,
+                    pattern = 'regex',
+                    option = 'i',
+                    format = {
+                      {
+                        type = snippet.NodeType.FORMAT,
+                        capture_index = 1,
+                        modifier = 'upcase'
+                      }
+                    }
+                  },
+                },
+                {
+                  type = snippet.NodeType.TEXT,
+                  raw = 'TE\\$\\}XT',
+                  esc = 'TE$}XT'
+                },
+              }
+            }
+          }
+        },
+      }
+    }, parse('${1:${2:TE\\$\\}XT$3${1/regex/${1:/upcase}/i}TE\\$\\}XT}}'))
+  end)
+
+  it('should parse variables', function()
+    eq({
+      type = snippet.NodeType.SNIPPET,
+      children = {
+        {
+          type = snippet.NodeType.VARIABLE,
+          name = 'VAR',
+        },
+        {
+          type = snippet.NodeType.VARIABLE,
+          name = 'VAR',
+        },
+        {
+          type = snippet.NodeType.VARIABLE,
+          name = 'VAR',
+          children = {
+            {
+              type = snippet.NodeType.TABSTOP,
+              tabstop = 1,
+            }
+          }
+        },
+        {
+          type = snippet.NodeType.VARIABLE,
+          name = 'VAR',
+          transform = {
+            type = snippet.NodeType.TRANSFORM,
+            pattern = 'regex',
+            format = {
+              {
+                type = snippet.NodeType.FORMAT,
+                capture_index = 1,
+                modifier = 'upcase',
+              }
+            }
+          }
+        },
+      }
+    }, parse('$VAR${VAR}${VAR:$1}${VAR/regex/${1:/upcase}/}'))
+  end)
+
+  it('should parse choice', function()
+    eq({
+      type = snippet.NodeType.SNIPPET,
+      children = {
+        {
+          type = snippet.NodeType.CHOICE,
+          tabstop = 1,
+          items = {
+            ',',
+            '|'
+          }
+        }
+      }
+    }, parse('${1|\\,,\\||}'))
+  end)
+
+end)
+