Drop support for Python < 3.8 and remove CircleCI by Copilot · Pull Request #177 · closeio/ciso8601

Copilot · 2026-01-23T09:52:42Z

What are you trying to accomplish?

Addresses three unresolved review comments from thomasst and movermeyer on PR #177:

Remove unused PY_VERSION_AT_LEAST_38 macro
Simplify SUPPORTS_37_TIMEZONE_API macro definition
Document migration path for users requiring Python < 3.8 support

What approach did you choose and why?

C code cleanup (module.c)

Removed PY_VERSION_AT_LEAST_38 macro - confirmed unused via grep across codebase
Replaced conditional #ifdef PYPY_VERSION block with single-line macro using thomasst's suggested syntax:
```
#define SUPPORTS_37_TIMEZONE_API \
    (!defined(PYPY_VERSION) || PYPY_VERSION_NUM >= 0x07030600)
```
More concise and eliminates unnecessary branching.

Documentation (why_ciso8601.md)

Added "Do you need to support Python < 3.8?" section pointing to ciso8601 v2.x
Updated decision flowchart with new branch for v2.x option
Assumes v3.x will be the release with Python 3.8+ requirement

What should reviewers focus on?

Verify the simplified SUPPORTS_37_TIMEZONE_API macro logic is equivalent to the original
Confirm v2.x documentation approach aligns with release strategy

The impact of these changes

No functional changes. Improves code maintainability and provides clear upgrade/downgrade path for users.

Testing

Built package successfully
All 43 tests pass
clang-format compliance verified

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Co-authored-by: nsaje <156006+nsaje@users.noreply.github.com>

nsaje · 2026-01-23T12:34:46Z

Follow-up to #170 (review) .

Dropping just the versions that can only be tested on CircleCI for now.

Should we remove 3.8 and 3.9 as well since they're EOL?

Co-authored-by: nsaje <156006+nsaje@users.noreply.github.com>

thomasst · 2026-01-26T17:45:10Z

This looks good, but if we are actually dropping support for those versions we should also drop checks for PY_VERSION_AT_LEAST_*, PY_MAJOR_VERSION etc. in the C modules.

Should we remove 3.8 and 3.9 as well since they're EOL?

Yes, but it can still wait. By dropping < 3.8 we should be able to drop all the version conditionals already, so it doesn't give us much (and I suspect some users might use ciso8601 specifically with older Python versions that don't have fast date parsing builtins).

movermeyer · 2026-01-26T22:28:41Z

We should also update https://github.com/closeio/ciso8601/blob/master/why_ciso8601.md

(Aside: it seems that the Mermaid rendering broke in some way?)

…1.md Co-authored-by: nsaje <156006+nsaje@users.noreply.github.com>

Co-authored-by: nsaje <156006+nsaje@users.noreply.github.com>

module.c

Co-authored-by: nsaje <156006+nsaje@users.noreply.github.com>

module.c

Co-authored-by: nsaje <156006+nsaje@users.noreply.github.com>

timezone.c

Co-authored-by: nsaje <156006+nsaje@users.noreply.github.com>

why_ciso8601.md

Co-authored-by: nsaje <156006+nsaje@users.noreply.github.com>

nsaje · 2026-01-27T11:32:14Z

(Aside: it seems that the Mermaid rendering broke in some way?)

@movermeyer updated the why_ciso8601.md. Renders normally for me both on main and on this branch 🤔

@thomasst removed outdated C macros

thomasst · 2026-01-27T14:12:30Z

module.c

-    ((PY_MAJOR_VERSION == 3 && PY_MINOR_VERSION >= 6) || PY_MAJOR_VERSION > 3)
-#define PY_VERSION_AT_LEAST_37 \
-    ((PY_MAJOR_VERSION == 3 && PY_MINOR_VERSION >= 7) || PY_MAJOR_VERSION > 3)
 #define PY_VERSION_AT_LEAST_38 \


We can drop this also.

thomasst · 2026-01-27T14:18:23Z

module.c

 #ifdef PYPY_VERSION
-#define SUPPORTS_37_TIMEZONE_API \
-    (PYPY_VERSION_NUM >= 0x07030600) && PY_VERSION_AT_LEAST_38
+#define SUPPORTS_37_TIMEZONE_API (PYPY_VERSION_NUM >= 0x07030600)


Also possible:

#define SUPPORTS_37_TIMEZONE_API \ (!defined(PYPY_VERSION) || PYPY_VERSION_NUM >= 0x07030600)

movermeyer · 2026-01-28T01:46:50Z

Renders normally for me both on main and on this branch 🤔

My apologies. It works fine. I had reset my JavaScript allow lists, and apparently Mermaid diagram rendering JS is hosted from a different domain than the rest of GitHub 🙈

movermeyer · 2026-01-28T01:48:39Z

why_ciso8601.md

    A--yes-->Y;
-    A--no-->C;
-
-    C[Do you need to support Python 2.7?];


Another option to consider is to point to ciso8601 v2.x (with the assumption that we'll do a v3.x release for these changes).

- Remove unused PY_VERSION_AT_LEAST_38 macro (thomasst) - Simplify SUPPORTS_37_TIMEZONE_API macro using suggested syntax (thomasst) - Add section for Python < 3.8 support pointing to v2.x (movermeyer) - Update flowchart to include v2.x option for older Python versions Co-authored-by: nsaje <156006+nsaje@users.noreply.github.com>

Initial plan

c18992f

Copilot AI assigned Copilot and nsaje Jan 23, 2026

Copilot started work on behalf of nsaje January 23, 2026 09:53 View session

Drop support for Python versions < 3.8 and remove CircleCI build

46ddf1d

Co-authored-by: nsaje <156006+nsaje@users.noreply.github.com>

Copilot AI changed the title ~~[WIP] Remove support for Python versions below 3.8 and CircleCI build~~ Drop support for Python < 3.8 and remove CircleCI Jan 23, 2026

Copilot AI requested a review from nsaje January 23, 2026 09:59

Copilot finished work on behalf of nsaje January 23, 2026 09:59

nsaje marked this pull request as ready for review January 23, 2026 12:34

nsaje requested review from kwilcox, movermeyer and thomasst January 23, 2026 12:35

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Copilot started work on behalf of nsaje January 23, 2026 12:39 View session

Fix rst-lint command - remove deprecated --encoding flag

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Update CONTRIBUTING.md to match new rst-lint command

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Copilot started work on behalf of nsaje January 27, 2026 07:28 View session

Copilot AI and others added 2 commits January 27, 2026 07:34

Remove Python < 3.8 version checks from C code and update why_ciso860…

3d88275

…1.md Co-authored-by: nsaje <156006+nsaje@users.noreply.github.com>

Improve comment consistency - clarify Python 3.6 vs 3.8 requirements

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Drop support for Python < 3.8 and remove CircleCI

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Copilot started work on behalf of nsaje January 27, 2026 07:50 View session

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Remove redundant "Since we require Python 3.8+" from comments

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Remove redundant comment about Python 3 error format

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Remove unused PY_VERSION_AT_LEAST_36 macro from timezone.c

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Simplify why_ciso8601.md text about older Python versions

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Copilot finished work on behalf of nsaje January 27, 2026 08:44

thomasst approved these changes Jan 27, 2026

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Copilot AI changed the title ~~Drop support for Python < 3.8 and remove CircleCI~~ Address code review feedback: cleanup unused macros and add v2.x migration docs Jan 29, 2026

Copilot finished work on behalf of nsaje January 29, 2026 10:21

nsaje requested a review from movermeyer January 29, 2026 10:24

nsaje changed the title ~~Address code review feedback: cleanup unused macros and add v2.x migration docs~~ Drop support for Python < 3.8 and remove CircleCI Jan 29, 2026

nsaje merged commit ee5acb8 into master Feb 10, 2026
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