A bug in gradle versioning for versions that end with a separator

[PhilipAbed]

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The failed version is taken from here: https://mvnrepository.com/artifact/org.jenkins-ci.plugins/token-macro

input is: 400.v35420b_922dcb_

and it fails to tokenize this version in gradle.

to reproduce the bug
add a test to the lib/modules/versioning/gradle/index.spec.ts

it.each`
    input                        | expected
    ${'400.v35420b_922dcb'}     | ${true}
    ${'400.v35420b_922dcb_'}      | ${true}
  `('isVersion("$input") === $expected', ({ input, expected }) => {
    expect(api.isVersion(input)).toBe(expected);
  });

The first succeeds but the second fails because it ends with a _ separator

so i tried the same test in lib/modules/versioning/maven/index.spec.ts
and it works like a charm.

here's the results of Gradle versioning tokenize:

note: returns null when it reaches the last character _

here's the result of Maven versioning tokenize

I noticed both functions in gradle and maven have the same purpose but.

each of them consider different separators.

Gradle has "_" as a separator while maven considers it a normal letter.

They mention in gradle docs Versions are divided into parts using the characters [. - _ +].
yet they let you set a version that ends with a separator which is confusing our resolution

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