1 files changed, 119 insertions, 0 deletions
diff --git a/test/functional/eval/executable_spec.lua b/test/functional/eval/executable_spec.lua
new file mode 100644
index 0000000000..dd8861a07c
--- /dev/null
+++ b/test/functional/eval/executable_spec.lua
@@ -0,0 +1,119 @@
+local helpers = require('test.functional.helpers')(after_each)
+local eq, clear, execute, call, iswin, write_file =
+  helpers.eq, helpers.clear, helpers.execute, helpers.call, helpers.iswin,
+  helpers.write_file
+
+describe('executable()', function()
+  before_each(clear)
+
+  it('returns 1 for commands in $PATH', function()
+    local exe = iswin() and 'ping' or 'ls'
+    eq(1, call('executable', exe))
+  end)
+
+  it('returns 0 for non-existent files', function()
+    eq(0, call('executable', 'no_such_file_exists_209ufq23f'))
+  end)
+
+  describe('exec-bit', function()
+    setup(function()
+      write_file('Xtest_not_executable', 'non-executable file')
+      write_file('Xtest_executable', 'executable file (exec-bit set)')
+      if not iswin() then  -- N/A for Windows.
+        call('system', {'chmod', '-x', 'Xtest_not_executable'})
+        call('system', {'chmod', '+x', 'Xtest_executable'})
+      end
+    end)
+
+    teardown(function()
+      os.remove('Xtest_not_executable')
+      os.remove('Xtest_executable')
+    end)
+
+    it('not set', function()
+      local expected = iswin() and 1 or 0
+      eq(expected, call('executable', 'Xtest_not_executable'))
+      eq(expected, call('executable', './Xtest_not_executable'))
+    end)
+
+    it('set, unqualified and not in $PATH', function()
+      local expected = iswin() and 1 or 0
+      eq(expected, call('executable', 'Xtest_executable'))
+    end)
+
+    it('set, qualified as a path', function()
+      eq(1, call('executable', './Xtest_executable'))
+    end)
+  end)
+end)
+
+describe('executable() (Windows)', function()
+  if not iswin() then return end  -- N/A for Unix.
+
+  local exts = {'bat', 'exe', 'com', 'cmd'}
+  setup(function()
+    for _, ext in ipairs(exts) do
+      write_file('test_executable_'..ext..'.'..ext, '')
+    end
+    write_file('test_executable_zzz.zzz', '')
+  end)
+
+  teardown(function()
+    for _, ext in ipairs(exts) do
+      os.remove('test_executable_'..ext..'.'..ext)
+    end
+    os.remove('test_executable_zzz.zzz')
+  end)
+
+  it('tries default extensions on a filename if $PATHEXT is empty', function()
+    -- Empty $PATHEXT defaults to ".com;.exe;.bat;.cmd".
+    clear({env={PATHEXT=''}})
+    for _,ext in ipairs(exts) do
+      eq(1, call('executable', 'test_executable_'..ext))
+    end
+    eq(0, call('executable', 'test_executable_zzz'))
+  end)
+
+  it('tries default extensions on a filepath if $PATHEXT is empty', function()
+    -- Empty $PATHEXT defaults to ".com;.exe;.bat;.cmd".
+    clear({env={PATHEXT=''}})
+    for _,ext in ipairs(exts) do
+      eq(1, call('executable', '.\\test_executable_'..ext))
+    end
+    eq(0, call('executable', '.\\test_executable_zzz'))
+  end)
+
+  it('respects $PATHEXT when trying extensions on a filename', function()
+    clear({env={PATHEXT='.zzz'}})
+    for _,ext in ipairs(exts) do
+      eq(0, call('executable', 'test_executable_'..ext))
+    end
+    eq(1, call('executable', 'test_executable_zzz'))
+  end)
+
+  it('respects $PATHEXT when trying extensions on a filepath', function()
+    clear({env={PATHEXT='.zzz'}})
+    for _,ext in ipairs(exts) do
+      eq(0, call('executable', '.\\test_executable_'..ext))
+    end
+    eq(1, call('executable', '.\\test_executable_zzz'))
+  end)
+
+  it('returns 1 for any existing filename', function()
+    clear({env={PATHEXT=''}})
+    for _,ext in ipairs(exts) do
+      eq(1, call('executable', 'test_executable_'..ext..'.'..ext))
+    end
+    eq(1, call('executable', 'test_executable_zzz.zzz'))
+  end)
+
+  it('returns 1 for any existing path (backslashes)', function()
+    clear({env={PATHEXT=''}})
+    for _,ext in ipairs(exts) do
+      eq(1, call('executable', '.\\test_executable_'..ext..'.'..ext))
+      eq(1, call('executable', './test_executable_'..ext..'.'..ext))
+    end
+    eq(1, call('executable', '.\\test_executable_zzz.zzz'))
+    eq(1, call('executable', './test_executable_zzz.zzz'))
+  end)
+end)