Harden REPL in presence of values that fail to initialize #14702
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The right hand side of value definitions in the REPL are computed in the static initializer for the wrapper object created for that input line (e.g. rs$line$1). If any of these definitions throws an exception, the wrapper class will fail to initialize, and further attempts to use the class will throw NoClassDefFoundError. In this commit, we avoid all reflective access on a wrapper class once we notice that it failed to initialize, and mark that wrapper object as invalid in the REPL state. We discard all input from the failed wrapper (which may have been multi-line containing many statements and definitions); any types, terms, aliases, or imports defined there will not override any existing with the same name, and will not be accessible in subsequent runs. Fixes scala#4416 Fixes scala#14473
…???` The REPL should not crash when the right hand side of `val _ =` throws a non-fatal error that is a subclass of java.lang.Error.
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The right hand side of value definitions in the REPL are computed in the static
initializer for the wrapper object created for that input line (e.g. rs$line$1).
If any of these definitions throws an exception, the wrapper class will fail to
initialize, and further attempts to use the class will throw NoClassDefFoundError.
In this PR, we avoid all reflective access on a wrapper class once we notice
that it failed to initialize, and mark that wrapper object as invalid in the REPL
state. We discard all input from the failed wrapper (which may have been multi-line
containing many statements and definitions); any types, terms, aliases, or imports
defined there will not override any existing with the same name, and will not be
accessible in subsequent runs.
We also avoid crashing the REPL when the input is of the form
val _ = ???,where the RHS throws any subclass of java.lang.Error that is non-fatal.
Fixes #4416
Fixes #14473
Fixes #14701