1 //===--- tools/extra/clang-tidy/GlobList.cpp ------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "GlobList.h"
10 #include "llvm/ADT/SmallString.h"
11 
12 using namespace clang;
13 using namespace tidy;
14 
15 // Returns true if GlobList starts with the negative indicator ('-'), removes it
16 // from the GlobList.
ConsumeNegativeIndicator(StringRef & GlobList)17 static bool ConsumeNegativeIndicator(StringRef &GlobList) {
18   GlobList = GlobList.trim(" \r\n");
19   if (GlobList.startswith("-")) {
20     GlobList = GlobList.substr(1);
21     return true;
22   }
23   return false;
24 }
25 
26 // Converts first glob from the comma-separated list of globs to Regex and
27 // removes it and the trailing comma from the GlobList.
ConsumeGlob(StringRef & GlobList)28 static llvm::Regex ConsumeGlob(StringRef &GlobList) {
29   StringRef UntrimmedGlob = GlobList.substr(0, GlobList.find(','));
30   StringRef Glob = UntrimmedGlob.trim(' ');
31   GlobList = GlobList.substr(UntrimmedGlob.size() + 1);
32   SmallString<128> RegexText("^");
33   StringRef MetaChars("()^$|*+?.[]\\{}");
34   for (char C : Glob) {
35     if (C == '*')
36       RegexText.push_back('.');
37     else if (MetaChars.contains(C))
38       RegexText.push_back('\\');
39     RegexText.push_back(C);
40   }
41   RegexText.push_back('$');
42   return llvm::Regex(RegexText);
43 }
44 
GlobList(StringRef Globs)45 GlobList::GlobList(StringRef Globs) {
46   Items.reserve(Globs.count(',') + 1);
47   do {
48     GlobListItem Item;
49     Item.IsPositive = !ConsumeNegativeIndicator(Globs);
50     Item.Regex = ConsumeGlob(Globs);
51     Items.push_back(std::move(Item));
52   } while (!Globs.empty());
53 }
54 
contains(StringRef S) const55 bool GlobList::contains(StringRef S) const {
56   // Iterating the container backwards as the last match determins if S is in
57   // the list.
58   for (const GlobListItem &Item : llvm::reverse(Items)) {
59     if (Item.Regex.match(S))
60       return Item.IsPositive;
61   }
62   return false;
63 }
64