Notes on what e2e testing will look like.

test_runner_e2e.py

@@ -0,0 +1,72 @@
+import shlex
+from subprocess import Popen, PIPE
+
+# We write test files in python. The test runner collects all python files in
+# the directory and executes them. The test function just creates a test object
+# which specifies expected stdin/stdout.
+#
+# Test functions are automatically discovered; they just need to be in the
+# global environment and start with `Test_`.
+
+class TestBuilder:
+  def WithFile(self, filename, contents):
+    """
+    Writes the file contents to disk so that the language server can access it.
+    """
+    pass
+
+  def Send(self, stdin):
+    """
+    Send the given message to the language server.
+    """
+
+    # Content-Length: ...\r\n
+    # \r\n
+    # {
+    #   "jsonrpc": "2.0",
+    #   "id": 1,
+    #   "method": "textDocument/didOpen",
+    #   "params": {
+    #     ...
+    #   }
+    # }
+
+  def Expect(self, stdout):
+    """
+    Expect a message from the language server.
+    """
+    pass
+
+  def SetupCommonInit():
+    """
+    Add initialize/initialized messages.
+    """
+    pass
+
+
+def Test_Outline():
+  return TestBuilder()
+    .SetupCommonInit()
+    .WithFile("foo.cc",
+      """
+      void main() {}
+      """
+    )
+    .Send({
+      'id': 1,
+      'method': 'textDocument/documentSymbol',
+      'params': {}
+    })
+    .Expect({
+      'id': 1
+      'result': [
+        lsSymbolInfo('void main()', (1, 1), lsSymbolKind.Function)
+      ]
+    })
+
+
+# Possible test runner implementation
+# cmd = "x64/Release/indexer.exe --language-server"
+# process = Popen(shlex.split(cmd), stdin=PIPE, stdout=PIPE)
+# process.communicate('{}')
+# exit_code = process.wait()