Fix bug in scientific notation parsing #711
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@@ Coverage Diff @@
## main #711 +/- ##
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+ Coverage 84.97% 85.36% +0.38%
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Files 54 54
Lines 5858 5855 -3
Branches 1338 1337 -1
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+ Hits 4978 4998 +20
+ Misses 597 576 -21
+ Partials 283 281 -2
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Benchmark resultsBefore this PR: 353.1 thousand lines per second Measured change: 0.06% faster (1.12% slower to 0.54% faster) |
Fixes #676 Scientific notation parsing was using the shared `readInt` code path, which I had made more flexible to handle hex digits, but that means that literals like `1e2` were being treated as a complete number (with the hex digit `e`) rather than as scientific notation. Normally this wouldn't be a problem since it's all a number token anyway, but it caused trouble when using dot-style property access like `1e2.toString()`. Expressions like `1.toString()` are expected to fail because `.` is interpreted as a decimal point, but when using scientific notation, the parser needs to be smart enough see that a decimal point wouldn't be valid, and therefore not include it as part of the token. The fix was to change `readInt` to only handle decimal digits, not hex digits, and to inline the hex case into `readRadixNumber`. This should make number parsing slightly faster because it's not checking for hex digits anymore.
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Fixes alangpierce#676 Scientific notation parsing was using the shared `readInt` code path, which I had made more flexible to handle hex digits, but that means that literals like `1e2` were being treated as a complete number (with the hex digit `e`) rather than as scientific notation. Normally this wouldn't be a problem since it's all a number token anyway, but it caused trouble when using dot-style property access like `1e2.toString()`. Expressions like `1.toString()` are expected to fail because `.` is interpreted as a decimal point, but when using scientific notation, the parser needs to be smart enough see that a decimal point wouldn't be valid, and therefore not include it as part of the token. The fix was to change `readInt` to only handle decimal digits, not hex digits, and to inline the hex case into `readRadixNumber`. This should make number parsing slightly faster because it's not checking for hex digits anymore.
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Fixes #676
Scientific notation parsing was using the shared
readIntcode path, which Ihad made more flexible to handle hex digits, but that means that literals like
1e2were being treated as a complete number (with the hex digite) ratherthan as scientific notation. Normally this wouldn't be a problem since it's all
a number token anyway, but it caused trouble when using dot-style property
access like
1e2.toString(). Expressions like1.toString()are expected tofail because
.is interpreted as a decimal point, but when using scientificnotation, the parser needs to be smart enough see that a decimal point wouldn't
be valid, and therefore not include it as part of the token.
The fix was to change
readIntto only handle decimal digits, not hex digits,and to inline the hex case into
readRadixNumber. This should make numberparsing slightly faster because it's not checking for hex digits anymore.
I also added some tests since some of this code wasn't well covered by test
coverage.