MySQL Processlist Idle-Session Boolean Fix Implementation Plan

For agentic workers: REQUIRED SUB-SKILL: Use superpowers:subagent-driven-development (recommended) or superpowers:executing-plans to implement this plan task-by-task. Steps use checkbox (- [ ]) syntax for tracking.

Goal: Make textual true enable idle MySQL sessions in stats_mysql_processlist after LOAD MYSQL VARIABLES TO RUNTIME, with an end-to-end TAP regression test.

Architecture: Preserve the existing processlist_config_t boundary. Correct the MySQL admin-side processlist copy when the special variable callback receives boolean text, then exercise the complete admin/config/session/processlist path through TAP.

Tech Stack: C++17, ProxySQL admin variable loading, MariaDB client TAP tests, groups.json CI registration.

Global Constraints

Only the MySQL processlist synchronization path is changed.
The test must use the textual true value and LOAD MYSQL VARIABLES TO RUNTIME.
The test must prove both the disabled and enabled visibility states for an idle client session.
Existing user changes outside this branch remain untouched.

Task 1: Add the failing TAP regression test

Files:

Create: test/tap/tests/reg_test_processlist_idle_boolean-t.cpp
Modify: test/tap/groups/groups.json

Interfaces:

Consumes: CommandLine, TAP helpers, MariaDB client API, ProxySQL admin SET/LOAD commands, and stats_mysql_processlist.
Produces: A registered TAP binary named reg_test_processlist_idle_boolean-t that fails on the current atoi("true") implementation.
Step 1: Write the test source before changing production code

Implement one test that:
1. Reads TAP connection settings and opens admin and frontend MySQL connections.
2. Sets mysql-session_idle_ms=1 and mysql-session_idle_show_processlist=false, then loads MySQL variables to runtime.
3. Opens a frontend session and records mysql_thread_id() without issuing another query.
4. Sleeps long enough for the session to move to an idle maintenance thread.
5. Queries SELECT COUNT(*) FROM stats_mysql_processlist WHERE SessionID=<id> and asserts zero rows while the flag is false.
6. Executes SET mysql-session_idle_show_processlist=true followed by LOAD MYSQL VARIABLES TO RUNTIME.
7. Queries the same count and asserts one row while the flag is the textual true.
8. Closes the frontend session and restores mysql-session_idle_show_processlist=true and mysql-session_idle_ms=1 through a final load.
The test must use TAP plan()/ok() assertions, free every stored result, and report query failures with diag() before returning a nonzero exit status.

Step 2: Register the test in every standard MySQL g1 group

Add the test name to the same group list used by kill_connection3-t:

json

"reg_test_processlist_idle_boolean-t" : [ "legacy-g1","mariadb10-galera-g1","mysql-auto_increment_delay_multiplex=0-g1","mysql-multiplexing=false-g1","mysql-query_digests=0-g1","mysql-query_digests_keep_comment=1-g1","mysql84-g1","mysql84-gr-g1","mysql90-g1","mysql90-gr-g1","mysql93-g1","mysql93-gr-g1","mysql95-g1","mysql95-gr-g1" ]

Step 3: Build and run only the new test to verify the expected failure

Run:
bash
```
make -C test/tap/tests reg_test_processlist_idle_boolean-t
./test/tap/tests/reg_test_processlist_idle_boolean-t
```
Expected: compilation succeeds when TAP dependencies are available, and the enabled assertion fails against the current implementation because atoi("true") leaves the admin-side flag disabled. If infrastructure or generated dependencies are unavailable, capture that exact limitation and use the source-level red/green validation below.

Task 2: Fix boolean synchronization

Files:

Modify: lib/Admin_FlushVariables.cpp:498-500

Interfaces:

Consumes: varvalue supplied by flush_GENERIC_variables__process__database_to_runtime() after GloMTH->set_variable() validates the MySQL variable.
Produces: Correct GloAdmin->variables.mysql_processlist.show_idle_session values for true, false, 1, and 0.
Step 1: Replace the numeric-only conversion

Change the MySQL callback assignment from:
cpp
```
GloAdmin->variables.mysql_processlist.show_idle_session = atoi(varvalue);
```
to a boolean conversion equivalent to:
cpp
```
GloAdmin->variables.mysql_processlist.show_idle_session =
    strcasecmp(varvalue, "true") == 0 || strcasecmp(varvalue, "1") == 0;
```
Keep the callback in the existing special-value list and do not alter the PostgreSQL processlist path in this focused fix.
Step 2: Rebuild and rerun the regression test

Run:
bash
```
make -C lib -j2
make -C src -j2
make -C test/tap/tests reg_test_processlist_idle_boolean-t
./test/tap/tests/reg_test_processlist_idle_boolean-t
```
Expected: the disabled assertion remains zero and the textual-true assertion reports the idle session.

Task 3: Validate repository integration

Files:

Validate: lib/Admin_FlushVariables.cpp, test/tap/tests/reg_test_processlist_idle_boolean-t.cpp, test/tap/groups/groups.json

Step 1: Run TAP registration and formatting checks

bash

python3 test/tap/groups/lint_groups_json.py
python3 test/tap/groups/check_groups.py --source
git diff --check

Step 2: Inspect the final diff and status

bash

git diff --stat
git diff -- lib/Admin_FlushVariables.cpp test/tap/tests/reg_test_processlist_idle_boolean-t.cpp test/tap/groups/groups.json
git status --short --branch

Confirm only the intended production file, TAP test, group registration, and implementation documents are present.

Step 3: Commit the implementation

bash

git add lib/Admin_FlushVariables.cpp test/tap/tests/reg_test_processlist_idle_boolean-t.cpp test/tap/groups/groups.json
git commit -m "fix: parse idle processlist boolean values"

Step 4: Run the final available verification commands

Repeat the targeted test/build commands that are supported by the environment and record any dependency or infrastructure limitation explicitly before requesting review and opening the PR.