Allow override pushChanges from terminal

[ssheikin]

mvn release:prepare -DpushChanges

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[ssheikin]

should other properties/methods from ReleaseDescriptorBuilder be overriden here too?

[kwin]

Isn't

maven-release/maven-release-plugin/src/main/java/org/apache/maven/plugins/release/AbstractScmReadWriteReleaseMojo.java

Line 104 in f06aaa2

descriptor.setPushChanges(pushChanges);

enough in the context of the prepare goal?

[ssheikin]

It's not enough.

PTAL on repro: https://github.com/ssheikin/maven-release-1394-repro#running-it

Also, let me share AI reasoning about it:

  Here's the actual Maven mechanism, in three steps.

  1. The annotation becomes a default expression in plugin.xml.
  @Parameter(defaultValue = "true", property = "pushChanges") (AbstractScmReadWriteReleaseMojo.java:79) is compiled by maven-plugin-tools into the plugin descriptor as a default configuration entry, roughly:

  <configuration>
    <pushChanges default-value="true">${pushChanges}</pushChanges>
  </configuration>

  So out of the box, the parameter's configured value is the expression ${pushChanges}. property is just "the name of the expression that goes in this slot."

  2. The POM <configuration> is merged on top of that descriptor default (a DOM merge).
  When your POM declares:

  <configuration><pushChanges>false</pushChanges></configuration>

  Maven merges it over the descriptor config with Xpp3Dom merge rules. Same element name → the POM's child replaces the descriptor's. The effective config for the mojo execution is now the literal:

  <pushChanges>false</pushChanges>   <!-- the ${pushChanges} expression is gone -->

  3. Configuration injection evaluates expressions — but there's no longer one.
  The component configurator walks the merged config and, for each ${...}, calls PluginParameterExpressionEvaluator, which is what resolves ${pushChanges} against session.getUserProperties() (your -D values).
  But after step 2 the value is the plain string "false" — no ${...}, nothing to evaluate, -D is never read. The field is set to false.

  So the rule is: -Dxxx only feeds a parameter whose configured value is still the ${xxx} expression — i.e. one you did not set explicitly in <configuration>. property supplies a default, it is not an override
  channel.

  Why it feels surprising: -DskipTests "always works" only because projects rarely hardcode <skipTests> in surefire's <configuration> — the ${skipTests} expression stays live. Hardcode
  <skipTests>false</skipTests> and -DskipTests=true is ignored the exact same way.

  Why that forces the fix where it is: once the literal wins, the mojo field is false, so descriptor.setPushChanges(pushChanges) can only ever propagate false. The raw -DpushChanges survives only as
  session.getUserProperties(), which reaches DefaultReleaseManager.prepare(...) as prepareRequest.getUserProperties() — hence the override must be applied there, not at the mojo.