varjujan added inline comments.
================ Comment at: clang-tools-extra/clang-tidy/readability/SuspiciousCallArgumentCheck.cpp:51 + {true, 40, 50}, // Substring. + {true, 50, 66}, // Levenshtein. + {true, 75, 85}, // Jaro-Winkler. ---------------- whisperity wrote: > aaron.ballman wrote: > > We should probably document where all these numbers come from, but `66` > > definitely jumps out at me as being a bit strange. :-D > Unfortunately, I have absolutely no idea. All these values are percentages > between 0 and 100 (`-1` is just saying that //"This heuristic doesn't accept > percentages"//), and this is written in the documentation now. However, the > answer to //"**why** 66%?"//, unless @varjujan can say something, I think is > lost to history... > > I'll read over his thesis once again, maybe I can find anything with regards > to this. > > Either way, I've detailed from both the code and the thesis how the > percentages are meant. In some cases, the % is calculated as //"% of the > longer string's length"//. In the Leventhstein's case, it's actually inverted: > > ``` > Dist = (1 - Dist / LongerLength) * 100; > ``` > > So what this says is that if the current arg1-param1 arg2-param2 pairing has > less than the inverse of 50% (which is more than 50%) of the longer string's > edit distance, but the arg2-param1 and arg1-param2 (the suggested swapped > order) has more than the inverse of 66% (which is less than 33%), then the > swap will be suggested. > > Originally these values were called `LowerBound` and `UpperBound`, > respectively, which was saying **even less** about what they mean... Sadly, I think there isn't any scientific reason behind these numbers. They just looked ok after a couple of test runs. (Maybe they make sense for shorter arg names, like the 66 for 3 char long names.) Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D20689/new/ https://reviews.llvm.org/D20689 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits