[2.x] fix: Fixes java++ tab completion#8778
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eed3si9n merged 10 commits intosbt:developfrom Feb 23, 2026
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- Limit optional-command completions after 'java++ ' to a small fixed list (-v, compile, test, run, clean, console, package) so JLine no longer prompts 'Display all 1114782 possibilities?'. - Add JavaSwitchCommandCompletions and use .examples(...) on the matched(combinedParser) token in switchParser. - Add CrossJavaTest test asserting the completion list is bounded and contains -v, compile, test. Fixes sbt#4310
…plus-completion - CrossJavaTest: use Fewer Braces for java++ completion test - Add scripted test that asserts java++ completions are bounded (<=100)
eed3si9n
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Feb 22, 2026
sbt-app/src/sbt-test/actions/java-plus-plus-completion/build.sbt
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Move .examples(JavaSwitchCommandCompletions*) from outside token() to inside on matched(state.combinedParser). The prior placement caused FixedSetExamples.withAddedPrefix to filter out all examples after the space character was derived, yielding zero completions after the user typed the space before the command. Remove actions/java-plus-plus-completion scripted test that called Parser.completions on the full state.combinedParser, which is too expensive and caused the CI job to timeout. The unit test in CrossJavaTest already covers the fix adequately.
eed3si9n
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Feb 23, 2026
Per review, the OOM comes from the version parser - token(StringBasic) on the right side of || has no examples constraint. Move .examples(knownVersions*) from the inner number parser to wrap the entire || expression, so both alternatives are bounded.
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Fixes #4310
Problem
Typing
java++(with space) and pressing Tab caused JLine to show "Display all 1114782 possibilities? (y or n)" because the optional-command argument usedmatched(state.combinedParser)with no completion limit.Solution
java++to a small fixed list:-v,compile,test,run,clean,console,package..examples(JavaSwitchCommandCompletions*)on the optional-command token inswitchParser(CrossJava.scala).CrossJavaTesttest that the completion list is bounded and contains key entries.Verification
./sbt "mainProj/Test/testOnly sbt.internal.CrossJavaTest"— all 16 tests pass (including "java++ tab completion list is bounded (Too many candidate list "java++" command tab completion #4310)").java++and Tab — completions are a short list, not "Display all N possibilities?".Root cause
optionalCommandwasParser.opt(token(Space ~> matched(state.combinedParser)));matched(combinedParser)delegates completions to the full sbt grammar, yielding millions of candidates.BasicCommands.reportParserandNetworkChannel.disconnect— cap completions via.examples(...).