[BUG] Increase pre* with pre-release identifiers without build

[pellmont]

What / Why

the semver package should be able to execute a increment premajor, preminor and prepatch for versioning schemes without a build number.
It for sure affects the standard maven versioning system (which is semver compliant).

Examples

Actual

0.0.1-SNAPSHOT premajor -> 1.0.0-SNAPSHOT.0
0.0.1-SNAPSHOT preminor -> 0.1.0-SNAPSHOT.0
0.0.1-SNAPSHOT prepatch -> 0.0.2-SNAPSHOT.0

Expected

0.0.1-SNAPSHOT premajor -> 1.0.0-SNAPSHOT
0.0.1-SNAPSHOT preminor -> 0.1.0-SNAPSHOT
0.0.1-SNAPSHOT prepatch -> 0.0.2-SNAPSHOT

Currently this package always sets a dot-separated build. I t would be desirable if the behavior could be chosen, or if it would at least respect the current versioning scheme.

[ljharb]

Wouldn’t that mean you can only ever have one snapshot per version? That seems a bit short-sighted.

[pellmont]

This is correct, for MAVEN repositories the SNAPSHOT versions are allowed to be updated. (internal it uses a timestamp for the different versions)

[ljharb]

sounds like a build number. Why isn’t it part of the version number?

[astellingwerf]

The whole idea of the snapshot version is that you don't need to update references to it with every new build. See also What is a SNAPSHOT version?.

[ljharb]

Wouldn’t a semver range like 1.2.3-SNAPSHOT.0 do that?

[ljharb]

Versions in semver are designed to be immutable - in other words, it’s not semver if it’s changing over time.

[astellingwerf]

1.2.3-SNAPSHOT is a perfectly valid semver. See this overview of the spec, where I marked the choices for the different options using >>> in front.

        <valid semver> ::= <version core>
>>>                      | <version core> "-" <pre-release>
                         | <version core> "+" <build>
                         | <version core> "-" <pre-release> "+" <build>

        <version core> ::= <major> "." <minor> "." <patch>

        <major> ::= <numeric identifier>

        <minor> ::= <numeric identifier>
        
        <patch> ::= <numeric identifier>

>>>     <pre-release> ::= <dot-separated pre-release identifiers>

>>>     <dot-separated pre-release identifiers> ::= <pre-release identifier>
                                                  | <pre-release identifier> "." <dot-separated pre-release identifiers>

        <build> ::= <dot-separated build identifiers>

        <dot-separated build identifiers> ::= <build identifier>
                                            | <build identifier> "." <dot-separated build identifiers>

>>>     <pre-release identifier> ::= <alphanumeric identifier>
                                   | <numeric identifier>

        <build identifier> ::= <alphanumeric identifier>
                             | <digits>

        <alphanumeric identifier> ::= <non-digit>
>>>                                 | <non-digit> <identifier characters>
                                    | <identifier characters> <non-digit>
                                    | <identifier characters> <non-digit> <identifier characters>

        <numeric identifier> ::= "0"
                               | <positive digit>
                               | <positive digit> <digits>

        <identifier characters> ::= <identifier character>
>>>                               | <identifier character> <identifier characters>

        <identifier character> ::= <digit>
>>>                              | <non-digit>

>>>     <non-digit> ::= <letter>
                      | "-"

        <digits> ::= <digit>
                   | <digit> <digits>

        <digit> ::= "0"
                  | <positive digit>

        <positive digit> ::= "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9"

>>>     <letter> ::= "A" | "B" | "C" | "D" | "E" | "F" | "G" | "H" | "I" | "J"
>>>                | "K" | "L" | "M" | "N" | "O" | "P" | "Q" | "R" | "S" | "T"
                   | "U" | "V" | "W" | "X" | "Y" | "Z" | "a" | "b" | "c" | "d"
                   | "e" | "f" | "g" | "h" | "i" | "j" | "k" | "l" | "m" | "n"
                   | "o" | "p" | "q" | "r" | "s" | "t" | "u" | "v" | "w" | "x"
                   | "y" | "z"

[ljharb]

Absolutely that string is valid semver. But its contents must never change - versions are immutable.

[astellingwerf]

Fair enough, but whether I adhere to that rule should not be a problem when reasoning about the semver version. If we have semver version number 1.2.3-anything, and we order node-semver to increment the minor component, there's no reason to fiddle with the pre-release identifier. It should return 1.3.3-anything.

[ljharb]

Fair enough.

the standard maven versioning system (which is semver compliant).

still worth establishing that it is not compliant, because snapshot contents change - and that by appending a .0, and relying on that instead, it would be, and this bug wouldn't apply.

[astellingwerf]

The semver 2.0.0 spec mentions "increment" 16 times, but only for the major, minor, and patch versions. In it, I didn't see instructions on adding significant figures to any of the elements.