tests/indent: refactor indent test runner and auto-discover language test files

lua/nvim-treesitter/test_utils.lua

@@ -3,20 +3,20 @@ local M = {}
 local assert = require('luassert')
 
 function M.set_buf_indent_opts(opts)
-    local optnames = {'tabstop', 'shiftwidth', 'softtabstop', 'expandtab'}
-    for _, opt in ipairs(optnames) do
-      if opts[opt] ~= nil then
-        vim.bo[opt] = opts[opt]
-      end
+  local optnames = {'tabstop', 'shiftwidth', 'softtabstop', 'expandtab', 'filetype'}
+  for _, opt in ipairs(optnames) do
+    if opts[opt] ~= nil then
+      vim.bo[opt] = opts[opt]
     end
+  end
 end
 
-function M.indent_whole_file(file, opts)
+function M.run_indent_test(file, runner, opts)
   assert.are.same(1, vim.fn.filereadable(file))
 
   -- load reference file
   vim.cmd(string.format('edit %s', file))
-  local reference = vim.api.nvim_buf_get_lines(0, 0, -1, true)
+  local before = vim.api.nvim_buf_get_lines(0, 0, -1, true)
 
   -- FIXME: why this is not set automatically?
   vim.bo.indentexpr = 'nvim_treesitter#indent()'
@@ -24,15 +24,24 @@ function M.indent_whole_file(file, opts)
 
   M.set_buf_indent_opts(opts)
 
-  -- indent the whole file
-  vim.cmd 'silent normal gg=G'
-  local indented =  vim.api.nvim_buf_get_lines(0, 0, -1, true)
+  -- perform the test
+  runner()
+
+  -- get file content after the test
+  local after = vim.api.nvim_buf_get_lines(0, 0, -1, true)
 
   -- clear any changes to avoid 'No write since last change (add ! to override)'
   vim.cmd 'edit!'
 
-  -- compare before and after
-  assert.are.same(reference, indented)
+  return before, after
+end
+
+function M.indent_whole_file(file, opts)
+  local before, after = M.run_indent_test(file, function()
+    vim.cmd 'silent normal gg=G'
+  end, opts)
+
+  assert.are.same(before, after)
 end
 
 return M

lua/tests/indent/c_spec.lua

@@ -1,18 +1,18 @@
 local whole_file = require('nvim-treesitter.test_utils').indent_whole_file
+local scan_dir = require('plenary.scandir').scan_dir
 
-describe('indent C', function()
-  local files = {
-    'basic.c',
-    'no_braces.c',
-  }
-  for _, file in ipairs(files) do
-    it(file, function()
-      whole_file('lua/tests/indent/c/' .. file, {
-        tabstop = 4,
-        shiftwidth = 4,
-        softtabstop = 0,
-        expandtab = true,
-      })
-    end)
-  end
+describe('indent C:', function()
+  describe('whole file:', function()
+    local files = scan_dir('lua/tests/indent/c');
+    for _, file in ipairs(files) do
+      it(vim.fn.fnamemodify(file, ':t'), function()
+        whole_file(file, {
+          tabstop = 4,
+          shiftwidth = 4,
+          softtabstop = 0,
+          expandtab = true,
+        })
+      end)
+    end
+  end)
 end)

lua/tests/indent/python_spec.lua

@@ -1,26 +1,18 @@
 local whole_file = require('nvim-treesitter.test_utils').indent_whole_file
+local scan_dir = require('plenary.scandir').scan_dir
 
-describe('indent python', function()
-  local files = {
-    'aligned_indent.py',
-    'basic_blocks.py',
-    'basic_collections.py',
-    'branches.py',
-    'comprehensions.py',
-    'control_flow.py',
-    'hanging_indent.py',
-    'join_lines.py',
-    'nested_collections.py',
-    'strings.py',
-  }
-  for _, file in ipairs(files) do
-    it(file, function()
-      whole_file('lua/tests/indent/python/' .. file, {
-        tabstop = 4,
-        shiftwidth = 4,
-        softtabstop = 0,
-        expandtab = true,
-      })
-    end)
-  end
+describe('indent Python:', function()
+  describe('whole file:', function()
+    local files = scan_dir('lua/tests/indent/python');
+    for _, file in ipairs(files) do
+      it(vim.fn.fnamemodify(file, ':t'), function()
+        whole_file(file, {
+          tabstop = 4,
+          shiftwidth = 4,
+          softtabstop = 0,
+          expandtab = true,
+        })
+      end)
+    end
+  end)
 end)

lua/tests/indent/rust_spec.lua

@@ -1,17 +1,18 @@
 local whole_file = require('nvim-treesitter.test_utils').indent_whole_file
+local scan_dir = require('plenary.scandir').scan_dir
 
-describe('indent rust', function()
-  local files = {
-    'basic.rs',
-  }
-  for _, file in ipairs(files) do
-    it(file, function()
-      whole_file('lua/tests/indent/rust/' .. file, {
-        tabstop = 4,
-        shiftwidth = 4,
-        softtabstop = 0,
-        expandtab = true,
-      })
-    end)
-  end
+describe('indent Rust:', function()
+  describe('whole file:', function()
+    local files = scan_dir('lua/tests/indent/rust');
+    for _, file in ipairs(files) do
+      it(vim.fn.fnamemodify(file, ':t'), function()
+        whole_file(file, {
+          tabstop = 4,
+          shiftwidth = 4,
+          softtabstop = 0,
+          expandtab = true,
+        })
+      end)
+    end
+  end)
 end)