repl: catch all errors during tab completion#15255
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The tab completion handler in `completePrefix` only caught `ParseError`, `EvalError`, `BadURL`, and `FileNotFound`. Other error types like `JSONParseError` (which derives from `Error`, not `EvalError`) escaped the catch block and propagated through editline's C code as undefined behavior, crashing the REPL. This happened when tab-completing expressions like `(builtins.fromJSON "invalid").` where evaluation throws a non-`EvalError` exception. This commit marks `completionCallback` and `listPossibleCallback` as `noexcept` with function-try-blocks that catch all exceptions at the C/C++ boundary, preventing any exception from reaching editline. Fixes NixOS#15133.
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This commit verifies that `writeFull` with `allowInterrupts=false` completes successfully when the interrupt flag is set. This prevents regressions like the one fixed by NixOS#15255 where `write()` called `checkInterrupt()` unconditionally.
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This commit verifies that `writeFull` with `allowInterrupts=false` completes successfully when the interrupt flag is set. This prevents regressions like the one fixed by NixOS#15255 where `write()` called `checkInterrupt()` unconditionally.
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repl: catch all errors during tab completion
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This commit verifies that `writeFull` with `allowInterrupts=false` completes successfully when the interrupt flag is set. This prevents regressions like the one fixed by NixOS#15255 where `write()` called `checkInterrupt()` unconditionally.
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Motivation
The tab completion handler in
completePrefixonly caughtParseError,EvalError,BadURL, andFileNotFound. Other error types likeJSONParseError(which derives fromError, notEvalError) escapedthe catch block and propagated through editline's C code as undefined
behavior, crashing the REPL. This happened when tab-completing
expressions like
(builtins.fromJSON "invalid").where evaluationthrows a non-
EvalErrorexception.This commit marks
completionCallbackandlistPossibleCallbackasnoexceptwith function-try-blocks that catch all exceptions at theC/C++ boundary, preventing any exception from reaching editline.
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