RFC 2279 states that, in UTF-8:
"The octet values FE and FF never appear."
RFC 3629 states that, in UTF-8:
"The octet values C0, C1, F5 to FF never appear."
Generalize the check to advance past invalid starting bytes for
a UTF-8 sequence to fix a crash in the lexer.
- Enhance PBD with a whereExpr/elseStmt field to hold this.
- Start parsing the pattern of let/var decls as a potentially refutable pattern. It becomes
a semantic error to use a refutable pattern without an 'else' (diagnostics not in place yet).
- Change validatePatternBindingDecl to use 'defer' instead of a goto to ensure cleanups on exit.
- Have it resolve the pattern in a PBD, rewriting it from expressions into pattern nodes when valid.
- Teach resolvePattern to handle TypedPatterns now that they can appear (wrapping) refutable patterns.
- Teach resolvePattern to handle refutable patterns in PBD's without initializers by emitting a diagnostic
instead of by barfing, fixing regressions on validation tests my previous patch caused, and fixing
two existing validation test crashers.
Sema, silgen, and more tests coming later.
Swift SVN r26706
Most tests were using %swift or similar substitutions, which did not
include the target triple and SDK. The driver was defaulting to the
host OS. Thus, we could not run the tests when the standard library was
not built for OS X.
Swift SVN r24504
