SERVER-56216: Add commit-queue checks for unresolved TODOs

(cherry picked from commit 272b9e0bd2425ae15766b198de0f6a1a522bf8d3)
(cherry picked from commit a8782fc7ea197dd31964be8f238c618d9a776a01)

2 files changed, 529 insertions, 0 deletions

diff --git a/buildscripts/tests/test_todo_check.py b/buildscripts/tests/test_todo_check.py
new file mode 100644
index 00000000000..b158c3b18fb
--- /dev/null
+++ b/buildscripts/tests/test_todo_check.py
@@ -0,0 +1,266 @@
+"""Unit tests for todo_check.py."""
+
+from __future__ import absolute_import
+
+import os
+import textwrap
+import unittest
+from tempfile import TemporaryDirectory
+
+from typing import Iterable
+
+import buildscripts.todo_check as under_test
+
+# pylint: disable=missing-docstring,invalid-name,unused-argument,no-self-use,protected-access
+
+
+def create_file_iterator(file_contents: str) -> Iterable[str]:
+    return textwrap.dedent(file_contents.strip()).splitlines()
+
+
+class TestTodo(unittest.TestCase):
+    def test_line_without_a_jira_issues(self):
+        content = "a line with some random text"
+        todo = under_test.Todo.from_line("file", 42, f"\n{content}\n\t\n")
+
+        self.assertEqual(todo.file_name, "file")
+        self.assertEqual(todo.line_number, 42)
+        self.assertEqual(todo.line, content)
+        self.assertIsNone(todo.ticket)
+
+    def test_line_with_a_server_ticket(self):
+        ticket = "SERVER-12345"
+        content = f"a line with {ticket} some random text"
+        todo = under_test.Todo.from_line("file", 42, f"\n{content}\n\t\n")
+
+        self.assertEqual(todo.file_name, "file")
+        self.assertEqual(todo.line_number, 42)
+        self.assertEqual(todo.line, content)
+        self.assertEqual(todo.ticket, ticket)
+
+    def test_line_with_a_wiredtiger_ticket(self):
+        ticket = "WT-5555"
+        content = f"a line with {ticket} some random text"
+        todo = under_test.Todo.from_line("file", 42, f"\n{content}\n\t\n")
+
+        self.assertEqual(todo.file_name, "file")
+        self.assertEqual(todo.line_number, 42)
+        self.assertEqual(todo.line, content)
+        self.assertEqual(todo.ticket, ticket)
+
+
+class TestTodoChecker(unittest.TestCase):
+    def test_todo_checker_starts_out_empty(self):
+        todos = under_test.TodoChecker()
+
+        self.assertEqual(len(todos.found_todos.no_tickets), 0)
+        self.assertEqual(len(todos.found_todos.with_tickets), 0)
+        self.assertEqual(len(todos.found_todos.by_file), 0)
+
+    def test_a_file_with_no_todos(self):
+        file_contents = """
+        line 0
+        line 1
+        this is the file contents.
+        
+        """
+        todos = under_test.TodoChecker()
+
+        todos.check_file("my file", create_file_iterator(file_contents))
+
+        self.assertEqual(len(todos.found_todos.no_tickets), 0)
+        self.assertEqual(len(todos.found_todos.with_tickets), 0)
+        self.assertEqual(len(todos.found_todos.by_file), 0)
+
+    def test_a_file_with_an_untagged_todo(self):
+        file_contents = """
+        line 0
+        line 1
+        /* todo this needs some updating */
+        this is the file contents.
+        """
+        todos = under_test.TodoChecker()
+
+        todos.check_file("my file", create_file_iterator(file_contents))
+
+        self.assertEqual(len(todos.found_todos.no_tickets), 1)
+        self.assertEqual(len(todos.found_todos.with_tickets), 0)
+        self.assertEqual(len(todos.found_todos.by_file), 1)
+
+        todo = todos.found_todos.no_tickets[0]
+        self.assertEqual(todo.file_name, "my file")
+        self.assertEqual(todo.line_number, 3)
+        self.assertEqual(todo.ticket, None)
+
+        self.assertEqual(todo, todos.found_todos.by_file["my file"][0])
+
+    def test_a_file_with_a_tagged_todo(self):
+        file_contents = """
+        line 0
+        line 1
+        line 2
+        /* TODO server-1234 this needs some updating */
+        this is the file contents.
+        """
+        todos = under_test.TodoChecker()
+
+        todos.check_file("my file", create_file_iterator(file_contents))
+
+        self.assertEqual(len(todos.found_todos.no_tickets), 0)
+        self.assertEqual(len(todos.found_todos.with_tickets), 1)
+        self.assertEqual(len(todos.found_todos.by_file), 1)
+
+        todo = todos.found_todos.with_tickets["SERVER-1234"][0]
+        self.assertEqual(todo.file_name, "my file")
+        self.assertEqual(todo.line_number, 4)
+        self.assertEqual(todo.ticket, "SERVER-1234")
+
+        self.assertEqual(todo, todos.found_todos.by_file["my file"][0])
+
+    def test_report_on_ticket_will_return_true_if_ticket_is_found(self):
+        file_contents = """
+        line 0
+        line 1
+        line 2
+        /* TODO server-1234 this needs some updating */
+        this is the file contents.
+        """
+        todos = under_test.TodoChecker()
+        todos.check_file("my file", create_file_iterator(file_contents))
+
+        self.assertTrue(todos.report_on_ticket("SERVER-1234"))
+
+    def test_report_on_ticket_will_return_false_if_ticket_is_not_found(self):
+        file_contents = """
+        line 0
+        line 1
+        line 2
+        /* TODO server-1234 this needs some updating */
+        this is the file contents.
+        """
+        todos = under_test.TodoChecker()
+        todos.check_file("my file", create_file_iterator(file_contents))
+
+        self.assertFalse(todos.report_on_ticket("SERVER-9876"))
+
+    def test_report_all_tickets_will_return_true_if_any_ticket_is_found(self):
+        file_contents = """
+        line 0
+        line 1
+        line 2
+        /* TODO server-1234 this needs some updating */
+        this is the file contents.
+        /* TODO server-54321 this also needs some updating */
+        """
+        todos = under_test.TodoChecker()
+        todos.check_file("my file", create_file_iterator(file_contents))
+
+        self.assertTrue(todos.report_on_all_tickets())
+
+    def test_report_all_tickets_will_return_false_if_no_ticket_is_found(self):
+        file_contents = """
+        line 0
+        line 1
+        line 2
+        this is the file contents.
+        """
+        todos = under_test.TodoChecker()
+        todos.check_file("my file", create_file_iterator(file_contents))
+
+        self.assertFalse(todos.report_on_all_tickets())
+
+
+class TestValidateCommitQueue(unittest.TestCase):
+    def test_revert_commits_should_not_fail(self):
+        commit_message = "Reverts commit SERVER-1234"
+        file_contents = """
+        line 0
+        line 1
+        line 2
+        /* TODO server-1234 this needs some updating */
+        this is the file contents.
+        /* TODO server-54321 this also needs some updating */
+        """
+        todos = under_test.TodoChecker()
+        todos.check_file("my file", create_file_iterator(file_contents))
+
+        self.assertFalse(todos.validate_commit_queue(commit_message))
+
+    def test_todos_associated_with_commit_message_should_be_found(self):
+        commit_message = "SERVER-1234 making a commit"
+        file_contents = """
+        line 0
+        line 1
+        line 2
+        /* TODO server-1234 this needs some updating */
+        this is the file contents.
+        /* TODO server-54321 this also needs some updating */
+        """
+        todos = under_test.TodoChecker()
+        todos.check_file("my file", create_file_iterator(file_contents))
+
+        self.assertTrue(todos.validate_commit_queue(commit_message))
+
+    def test_commit_messages_with_multiple_commits_search_all_of_them(self):
+        commit_message = """
+        Making a wiredtiger drop
+        
+        WT-1234
+        WT-4321
+        WT-9876
+        """
+        file_contents = """
+        line 0
+        line 1
+        line 2
+        /* TODO server-1234 this needs some updating */
+        this is the file contents.
+        /* TODO WT-9876 this also needs some updating */
+        """
+        todos = under_test.TodoChecker()
+        todos.check_file("my file", create_file_iterator(file_contents))
+
+        self.assertTrue(todos.validate_commit_queue(commit_message))
+
+    def test_commit_messages_with_no_tickets_doesnt_cause_issues(self):
+        commit_message = "A random commit"
+        file_contents = """
+        line 0
+        line 1
+        line 2
+        /* TODO server-1234 this needs some updating */
+        this is the file contents.
+        /* TODO WT-9876 this also needs some updating */
+        """
+        todos = under_test.TodoChecker()
+        todos.check_file("my file", create_file_iterator(file_contents))
+
+        self.assertFalse(todos.validate_commit_queue(commit_message))
+
+
+def write_file(path: str, contents: str):
+    with open(path, "w") as fh:
+        fh.write(contents)
+
+
+class TestWalkFs(unittest.TestCase):
+    def test_walk_fs_walks_the_fs(self):
+        expected_files = {
+            "file1.txt": "The contents of file 1",
+            "file2.txt": "The contents of file 2",
+        }
+        with TemporaryDirectory() as tmpdir:
+            write_file(os.path.join(tmpdir, "file1.txt"), expected_files["file1.txt"])
+            os.makedirs(os.path.join(tmpdir, "dir0", "dir1"))
+            write_file(
+                os.path.join(tmpdir, "dir0", "dir1", "file2.txt"), expected_files["file2.txt"])
+
+            seen_files = {}
+
+            def visit_file(file_name, file_contents):
+                base_name = os.path.basename(file_name)
+                seen_files[base_name] = "\n".join(file_contents)
+
+            under_test.walk_fs(tmpdir, visit_file)
+
+            self.assertDictEqual(expected_files, seen_files)
diff --git a/buildscripts/todo_check.py b/buildscripts/todo_check.py
new file mode 100644
index 00000000000..314d4b2d284
--- /dev/null
+++ b/buildscripts/todo_check.py
@@ -0,0 +1,263 @@
+#!/usr/bin/env python3
+"""Check for TODOs in the source code."""
+import os
+import re
+import sys
+from collections import defaultdict
+from dataclasses import dataclass
+from typing import Iterable, Callable, Optional, NamedTuple, Dict, List
+
+import click
+
+BASE_SEARCH_DIR = "."
+ISSUE_RE = re.compile('(BUILD|SERVER|WT|PM|TOOLS|TIG|PERF|BF)-[0-9]+')
+
+
+class Todo(NamedTuple):
+    """
+    A TODO comment found the in the code.
+
+    file_name: Name of file comment was found in.
+    line_number: Line number comment was found in.
+    line: Content of line comment was found in.
+    ticket: Jira ticket associated with comment.
+    """
+
+    file_name: str
+    line_number: int
+    line: str
+    ticket: Optional[str] = None
+
+    @classmethod
+    def from_line(cls, file_name: str, line_number: int, line: str) -> "Todo":
+        """
+        Create a found todo from the given line of code.
+
+        :param file_name: File name comment was found in.
+        :param line_number: Line number comment was found in.
+        :param line: Content of line.
+        :return: Todo representation of found comment.
+        """
+        issue_key = cls.get_issue_key_from_line(line)
+        return cls(file_name, line_number, line.strip(), issue_key)
+
+    @staticmethod
+    def get_issue_key_from_line(line: str) -> Optional[str]:
+        """
+        Check if the given line appears to reference a jira ticket.
+
+        :param line: Content of line.
+        :return: Jira ticket if one was found.
+        """
+        match = ISSUE_RE.search(line.upper())
+        if match:
+            return match.group(0)
+        return None
+
+
+@dataclass
+class FoundTodos:
+    """
+    Collection of TODO comments found in the code base.
+
+    no_tickets: TODO comments found without any Jira ticket references.
+    with_tickets: Dictionary of Jira tickets references with a list of references.
+    by_file: All the references found mapped by the files they were found in.
+    """
+
+    no_tickets: List[Todo]
+    with_tickets: Dict[str, List[Todo]]
+    by_file: Dict[str, List[Todo]]
+
+
+class TodoChecker:
+    """A tool to find and track TODO references."""
+
+    def __init__(self) -> None:
+        """Initialize a new TODO checker."""
+        self.found_todos = FoundTodos(no_tickets=[], with_tickets=defaultdict(list),
+                                      by_file=defaultdict(list))
+
+    def check_file(self, file_name: str, file_contents: Iterable[str]) -> None:
+        """
+        Check the given file for TODO references.
+
+        Any TODOs will be added to `found_todos`.
+
+        :param file_name: Name of file being checked.
+        :param file_contents: Iterable of the file contents.
+        """
+        for i, line in enumerate(file_contents):
+            if "todo" in line.lower():
+                todo = Todo.from_line(file_name, i + 1, line)
+                if todo.ticket is not None:
+                    self.found_todos.with_tickets[todo.ticket].append(todo)
+                else:
+                    self.found_todos.no_tickets.append(todo)
+                self.found_todos.by_file[file_name].append(todo)
+
+    def check_all_files(self, base_dir: str) -> None:
+        """
+        Check all files under the base directory for TODO references.
+
+        :param base_dir: Base directory to start searching.
+        """
+        walk_fs(base_dir, self.check_file)
+
+    @staticmethod
+    def print_todo_list(todo_list: List[Todo]) -> None:
+        """Display all the TODOs in the given list."""
+        last_file = None
+        for todo in todo_list:
+            if last_file != todo.file_name:
+                print(f"{todo.file_name}")
+            print(f"\t{todo.line_number}: {todo.line}")
+
+    def report_on_ticket(self, ticket: str) -> bool:
+        """
+        Report on any TODOs found referencing the given ticket.
+
+        Any found references will be printed to stdout.
+
+        :param ticket: Jira ticket to search for.
+        :return: True if any TODOs were found.
+        """
+        todo_list = self.found_todos.with_tickets.get(ticket)
+        if todo_list:
+            print(f"{ticket}")
+            self.print_todo_list(todo_list)
+            return True
+        return False
+
+    def report_on_all_tickets(self) -> bool:
+        """
+        Report on all TODOs found that reference a Jira ticket.
+
+        Any found references will be printed to stdout.
+
+        :return: True if any TODOs were found.
+        """
+        if not self.found_todos.with_tickets:
+            return False
+
+        for ticket in self.found_todos.with_tickets.keys():
+            self.report_on_ticket(ticket)
+
+        return True
+
+    def validate_commit_queue(self, commit_message: str) -> bool:
+        """
+        Check that the given commit message does not reference TODO comments.
+
+        :param commit_message: Commit message to check.
+        :return: True if any TODOs were found.
+        """
+        print("*" * 80)
+        print("Checking for TODOs associated with Jira key in commit message.")
+        if "revert" in commit_message.lower():
+            print("Skipping checks since it looks like this is a revert.")
+            # Reverts are a special case and we shouldn't fail them.
+            return False
+
+        found_any = False
+        ticket = Todo.get_issue_key_from_line(commit_message)
+        while ticket:
+            found_any = self.report_on_ticket(ticket) or found_any
+            rest_index = commit_message.find(ticket)
+            commit_message = commit_message[rest_index + len(ticket):]
+            ticket = Todo.get_issue_key_from_line(commit_message)
+
+        print(f"Checking complete - todos found: {found_any}")
+        print("*" * 80)
+        return found_any
+
+
+def walk_fs(root: str, action: Callable[[str, Iterable[str]], None]) -> None:
+    """
+    Walk the file system and perform the given action on each file.
+
+    :param root: Base to start walking the filesystem.
+    :param action: Action to perform on each file.
+    """
+    for base, _, files in os.walk(root):
+        for file_name in files:
+            try:
+                file_path = os.path.join(base, file_name)
+                with open(file_path) as search_file:
+                    action(file_path, search_file)
+            except UnicodeDecodeError:
+                # If we try to read any non-text files.
+                continue
+
+
+@click.command()
+@click.option("--ticket", help="Only report on TODOs associated with given Jira ticket.")
+@click.option("--base-dir", default=BASE_SEARCH_DIR, help="Base directory to search in.")
+@click.option("--commit-message",
+              help="For commit-queue execution only, ensure no TODOs for this commit")
+def main(ticket: Optional[str], base_dir: str, commit_message: Optional[str]):
+    """
+    Search for and report on TODO comments in the code base.
+
+    Based on the arguments given, there are two types of searches you can perform:
+
+    \b
+    * By default, search for all TODO comments that reference any Jira ticket.
+    * Search for references to a specific Jira ticket with the `--ticket` option.
+
+    \b
+    Examples
+    --------
+
+        \b
+        Search all TODO comments with Jira references:
+        ```
+        > python buildscripts/todo_check.py
+        SERVER-12345
+        ./src/mongo/db/file.cpp
+            140: // TODO: SERVER-12345: Need to fix this.
+            183: // TODO: SERVER-12345: Need to fix this as well.
+        SERVER-54321
+        ./src/mongo/db/other_file.h
+            728: // TODO: SERVER-54321 an update is needed here
+        ```
+
+        \b
+        Search for any TODO references to a given ticket.
+        ```
+        > python buildscripts/todo_check.py --ticket SERVER-56197
+        SERVER-56197
+        ./src/mongo/db/query/query_feature_flags.idl
+            33: # TODO SERVER-56197: Remove feature flag.
+        ```
+
+    \b
+    Exit Code
+    ---------
+        In any mode, if any TODO comments are found a non-zero exit code will be returned.
+    \f
+    :param ticket: Only report on TODOs associated with this jira ticket.
+    :param base_dir: Search files in this base directory.
+    :param commit_message: Commit message if running in the commit-queue.[
+
+    """
+    if commit_message and ticket is not None:
+        raise click.UsageError("--ticket cannot be used in commit queue.")
+
+    todo_checker = TodoChecker()
+    todo_checker.check_all_files(base_dir)
+
+    if commit_message:
+        found_todos = todo_checker.validate_commit_queue(commit_message)
+    elif ticket:
+        found_todos = todo_checker.report_on_ticket(ticket)
+    else:
+        found_todos = todo_checker.report_on_all_tickets()
+
+    if found_todos:
+        sys.exit(1)
+    sys.exit(0)
+
+
+if __name__ == "__main__":
+    main()  # pylint: disable=no-value-for-parameter