[`pyupgrade`] Handle micro version numbers correctly (`UP036`) (#16091)

## Summary

Resolves #16082.

`UP036` will now also take into consideration whether or not a micro
version number is set:

* If a third element doesn't exist, the existing logic is preserved.
* If it exists but is not an integer literal, the check will not be
reported.
* If it is an integer literal but doesn't fit into a `u8`, the check
will be reported as invalid.
* Otherwise, the compared version is determined to always be less than
the target version when:
	* The target's minor version is smaller than that of the comparator, or
* The operator is `<`, the micro version is 0, and the two minor
versions compare equal.

As this is considered a bugfix, it is not preview-gated.

## Test Plan

`cargo nextest run` and `cargo insta test`.

---------

Co-authored-by: Micha Reiser <micha@reiser.io>

crates/ruff_linter/resources/test/fixtures/pyupgrade/UP036_5.py

@@ -28,3 +28,46 @@ else:
         else:
             print(3)
         return None
+
+
+# https://github.com/astral-sh/ruff/issues/16082
+
+## Errors
+if sys.version_info < (3, 12, 0):
+    print()
+
+if sys.version_info <= (3, 12, 0):
+    print()
+
+if sys.version_info < (3, 12, 11):
+    print()
+
+if sys.version_info < (3, 13, 0):
+    print()
+
+if sys.version_info <= (3, 13, 100000):
+    print()
+
+
+## No errors
+
+if sys.version_info <= (3, 13, foo):
+    print()
+
+if sys.version_info <= (3, 13, 'final'):
+    print()
+
+if sys.version_info <= (3, 13, 0):
+    print()
+
+if sys.version_info < (3, 13, 37):
+    print()
+
+if sys.version_info <= (3, 13, 37):
+    print()
+
+if sys.version_info <= (3, 14, 0):
+    print()
+
+if sys.version_info <= (3, 14, 15):
+    print()

crates/ruff_linter/src/rules/pyupgrade/rules/outdated_version_block.rs

@@ -236,14 +236,27 @@ fn version_always_less_than(
                 return Err(anyhow::anyhow!("invalid minor version: {if_minor}"));
             };
 
+            let if_micro = match check_version_iter.next() {
+                None => None,
+                Some(micro) => match micro.as_u8() {
+                    Some(micro) => Some(micro),
+                    None => anyhow::bail!("invalid micro version: {micro}"),
+                },
+            };
+
             Ok(if or_equal {
                 // Ex) `sys.version_info <= 3.8`. If Python 3.8 is the minimum supported version,
                 // the condition won't always evaluate to `false`, so we want to return `false`.
                 if_minor < py_minor
             } else {
-                // Ex) `sys.version_info < 3.8`. If Python 3.8 is the minimum supported version,
+                if let Some(if_micro) = if_micro {
-                // the condition _will_ always evaluate to `false`, so we want to return `true`.
+                    // Ex) `sys.version_info < 3.8.3`
-                if_minor <= py_minor
+                    if_minor < py_minor || if_minor == py_minor && if_micro == 0
+                } else {
+                    // Ex) `sys.version_info < 3.8`. If Python 3.8 is the minimum supported version,
+                    // the condition _will_ always evaluate to `false`, so we want to return `true`.
+                    if_minor <= py_minor
+                }
             })
         }
     }

crates/ruff_linter/src/rules/pyupgrade/snapshots/ruff_linter__rules__pyupgrade__tests__UP036_5.py.snap

@@ -66,3 +66,94 @@ UP036_5.py:18:4: UP036 [*] Version block is outdated for minimum Python version
    23 |+    else:
    24 |+        print(3)
    25 |+    return None
+31 26 | 
+32 27 | 
+33 28 | # https://github.com/astral-sh/ruff/issues/16082
+
+UP036_5.py:36:4: UP036 [*] Version block is outdated for minimum Python version
+   |
+35 | ## Errors
+36 | if sys.version_info < (3, 12, 0):
+   |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ UP036
+37 |     print()
+   |
+   = help: Remove outdated version block
+
+ℹ Unsafe fix
+33 33 | # https://github.com/astral-sh/ruff/issues/16082
+34 34 | 
+35 35 | ## Errors
+36    |-if sys.version_info < (3, 12, 0):
+37    |-    print()
+38 36 | 
+39 37 | if sys.version_info <= (3, 12, 0):
+40 38 |     print()
+
+UP036_5.py:39:4: UP036 [*] Version block is outdated for minimum Python version
+   |
+37 |     print()
+38 |
+39 | if sys.version_info <= (3, 12, 0):
+   |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ UP036
+40 |     print()
+   |
+   = help: Remove outdated version block
+
+ℹ Unsafe fix
+36 36 | if sys.version_info < (3, 12, 0):
+37 37 |     print()
+38 38 | 
+39    |-if sys.version_info <= (3, 12, 0):
+40    |-    print()
+41 39 | 
+42 40 | if sys.version_info < (3, 12, 11):
+43 41 |     print()
+
+UP036_5.py:42:4: UP036 [*] Version block is outdated for minimum Python version
+   |
+40 |     print()
+41 |
+42 | if sys.version_info < (3, 12, 11):
+   |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ UP036
+43 |     print()
+   |
+   = help: Remove outdated version block
+
+ℹ Unsafe fix
+39 39 | if sys.version_info <= (3, 12, 0):
+40 40 |     print()
+41 41 | 
+42    |-if sys.version_info < (3, 12, 11):
+43    |-    print()
+44 42 | 
+45 43 | if sys.version_info < (3, 13, 0):
+46 44 |     print()
+
+UP036_5.py:45:4: UP036 [*] Version block is outdated for minimum Python version
+   |
+43 |     print()
+44 |
+45 | if sys.version_info < (3, 13, 0):
+   |    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ UP036
+46 |     print()
+   |
+   = help: Remove outdated version block
+
+ℹ Unsafe fix
+42 42 | if sys.version_info < (3, 12, 11):
+43 43 |     print()
+44 44 | 
+45    |-if sys.version_info < (3, 13, 0):
+46    |-    print()
+47 45 | 
+48 46 | if sys.version_info <= (3, 13, 100000):
+49 47 |     print()
+
+UP036_5.py:48:24: UP036 Version specifier is invalid
+   |
+46 |     print()
+47 |
+48 | if sys.version_info <= (3, 13, 100000):
+   |                        ^^^^^^^^^^^^^^^ UP036
+49 |     print()
+   |