[QUESTION] Very confusing behavior for pre-release range matching

[robross0606]

When checking pre-release ranges, the results are very confusing. I have read the documentation many times, run a bunch of tests and reviewed all bug tickets. There are several open and closed issues that seem related to this, but I still can't figure out how this is expected to work. For example:

npx semver --range ">=1.0.2-0" "1.0.3-6"

Results in a non-match. Why if the range is ">=" and the range explicitly includes prereleases via "-0"? This seems to be incorrect.

npx semver --range "^1.0.2-0" "1.0.3-6"

Also results in a non-match. This seems to also be incorrect.

npx semver --range "^1.0.2-0" "1.0.3"

Results in a match. This is correct, but doesn't make sense that this would match when "1.0.3-6" does not.

 npx semver --range ">=1.0.2-0" "1.0.2-6"

Results in a match. This is correct.

So then I looked at using --include-prerelease. This seemed like the right approach based on the "Prerelease Tags" section in the README. However, this causes behavior to seem incorrect in the other extreme:

npx semver --include-prerelease --range "^1.0.2" "1.0.3-6"

Results in a match. Wait, what? This seems to completely contradict motivation expressed in the "Prerelease Tags" section.

So how can this be used effectively in automation to match versions in situations where we do want to include pre-releases from those where we do not if we cannot express that purely from the range expression itself? It seems to me that, the way this is designed, the range expression is barely (if at all) being used to decide if pre-releases are included.

[robross0606]

Even more inexplicable...

npx semver --include-prerelease --range ">=1.0.2" "1.0.3-6"

Results in a match. But this doesn't?!

npx semver --include-prerelease --range ">=1.0.2" "1.0.2-6"

But this does match:

npx semver --include-prerelease --range ">=1.0.2-0" "1.0.2-6"

And so does this:

npx semver --range ">=1.0.2-0" "1.0.2-6"

😵

I can understand almost every behavior except this one:

npx semver --include-prerelease --range ">=1.0.2" "1.0.2-6"

If I'm explicitly asking to include prereleases, then why would "1.0.2-6" not match while "1.0.3-6" does match? That behavior is baffling to me. That doesn't seem to consistently follow the README which states:

Note that this behavior can be suppressed (treating all prerelease versions as if they were normal versions, for range-matching) by setting the includePrerelease flag on the options object to any functions that do range matching.

[robross0606]

And it gets even weirder...
This matches:

npx semver --range "1.x.x-x" "1.0.2"

But this doesn't match:

npx semver --range "1.x.x-x" "1.0.2-6"

Nor does this:

npx semver --include-prereleases --range "1.x.x-x" "1.0.2-6"

I'm not sure if this is following some set of rules I just don't understand, or if range matching is buggy.