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[PATCH v3 0/6] Fun with cpp word regex

From
Johannes Sixt via GitGitGadget <gitgitgadget@gmail.com>
Date
Oct 10, 2021, 17:02 UTC
Message-ID
<pull.1054.v3.git.1633885384.gitgitgadget@gmail.com>
In-Reply-To
<pull.1054.v2.git.1633720197.gitgitgadget@gmail.com>

The cpp word regex driver is a bit too loose and can match too much text where the intent is to match only a number.

The first patch makes the cpp word regex tests more effective.

The second patch adds problematic test cases. The third patch fixes these problems.

The remaining three patches add support for digit separators and the spaceship operator <=> (generalized comparison operator).

I left out support for hexadecimal floating point constants because that would require to tighten the regex even more to avoid that entire expressions are treated as single tokens.

Changes since V2:
 * Add test cases for the new features in a separate commit so that the new
   behavior is better visible.
 * Don't treat .' as in '.' as a token.
Changes since V1:
 * Tests, tests, tests.
 * Polished commit messages.
Johannes Sixt (6):
  t4034/cpp: actually test that operator tokens are not split
  t4034: add tests showing problematic cpp tokenizations
  userdiff-cpp: tighten word regex
  userdiff-cpp: prepare test cases with yet unsupported features
  userdiff-cpp: permit the digit-separating single-quote in numbers
  userdiff-cpp: learn the C++ spaceship operator
 t/t4034/cpp/expect | 63 +++++++++++++++++++++++-----------------------
 t/t4034/cpp/post   | 47 +++++++++++++++++++++-------------
 t/t4034/cpp/pre    | 41 +++++++++++++++++++-----------
 userdiff.c         | 10 ++++++--
 4 files changed, 94 insertions(+), 67 deletions(-)
base-commit: 225bc32a989d7a22fa6addafd4ce7dcd04675dbf
Published-As: https://github.com/gitgitgadget/git/releases/tag/pr-1054%2Fj6t%2Ffun-with-cpp-word-regex-v3
Fetch-It-Via: git fetch https://github.com/gitgitgadget/git pr-1054/j6t/fun-with-cpp-word-regex-v3
Pull-Request: https://github.com/gitgitgadget/git/pull/1054
Range-diff vs v2:
 1:  dd9f82ba712 = 1:  dd9f82ba712 t4034/cpp: actually test that operator tokens are not split
 2:  5a84fc9cf71 = 2:  5a84fc9cf71 t4034: add tests showing problematic cpp tokenizations
 3:  d4ebe45fddc = 3:  d4ebe45fddc userdiff-cpp: tighten word regex
 4:  dd75d19cee9 ! 4:  c9f58b5e82f userdiff-cpp: permit the digit-separating single-quote in numbers
     @@ Metadata
      Author: Johannes Sixt <j6t@kdbg.org>
      
       ## Commit message ##
     -    userdiff-cpp: permit the digit-separating single-quote in numbers
     +    userdiff-cpp: prepare test cases with yet unsupported features
      
     -    Since C++17, the single-quote can be used as digit separator:
     -
     -       3.141'592'654
     -       1'000'000
     -       0xdead'beaf
     -
     -    Make it known to the word regex of the cpp driver, so that numbers are
     -    not split into separate tokens at the single-quotes.
     +    We are going to add support for C++'s digit-separating single-quote and
     +    the spaceship operator. By adding the test cases in this separate
     +    commit, the effect on the word highlighting will become more obvious
     +    as the features are implemented and the file cpp/expect is updated.
      
          Signed-off-by: Johannes Sixt <j6t@kdbg.org>
      
     @@ t/t4034/cpp/expect
      @@
       <BOLD>diff --git a/pre b/post<RESET>
      -<BOLD>index 1229cdb..3feae6f 100644<RESET>
     -+<BOLD>index 60f3640..f6fbf7b 100644<RESET>
     ++<BOLD>index 144cd98..64e78af 100644<RESET>
       <BOLD>--- a/pre<RESET>
       <BOLD>+++ b/post<RESET>
       <CYAN>@@ -1,30 +1,30 @@<RESET>
     -@@ t/t4034/cpp/expect: Foo() : x(0<RED>&&1<RESET><GREEN>&42<RESET>) { <RED>foo0<RESET><GREEN>bar<RESET>
     + Foo() : x(0<RED>&&1<RESET><GREEN>&42<RESET>) { <RED>foo0<RESET><GREEN>bar<RESET>(x.<RED>find<RESET><GREEN>Find<RESET>); }
       cout<<"Hello World<RED>!<RESET><GREEN>?<RESET>\n"<<endl;
     - <GREEN>(<RESET>1 <RED>-<RESET><GREEN>+<RESET>1e10 0xabcdef<GREEN>)<RESET> '<RED>x<RESET><GREEN>y<RESET>'
     +-<GREEN>(<RESET>1 <RED>-<RESET><GREEN>+<RESET>1e10 0xabcdef<GREEN>)<RESET> '<RED>x<RESET><GREEN>y<RESET>'
     ++<GREEN>(<RESET>1 <RED>-<RESET><GREEN>+<RESET>1e10 0xabcdef<GREEN>)<RESET> '<RED>x<RESET><GREEN>.<RESET>'
       // long double<RESET>
      -<RED>3.141592653e-10l<RESET><GREEN>3.141592654e+10l<RESET>
     -+<RED>3.141'592'653e-10l<RESET><GREEN>3.141'592'654e+10l<RESET>
     ++3.141'592'<RED>653e-10l<RESET><GREEN>654e+10l<RESET>
       // float<RESET>
       <RED>120E5f<RESET><GREEN>120E6f<RESET>
       // hex<RESET>
      -<RED>0xdeadbeaf<RESET><GREEN>0xdeadBeaf<RESET>+<RED>8ULL<RESET><GREEN>7ULL<RESET>
     -+<RED>0xdead'beaf<RESET><GREEN>0xdead'Beaf<RESET>+<RED>8ULL<RESET><GREEN>7ULL<RESET>
     ++0xdead'<RED>beaf<RESET><GREEN>Beaf<RESET>+<RED>8ULL<RESET><GREEN>7ULL<RESET>
       // octal<RESET>
      -<RED>01234567<RESET><GREEN>01234560<RESET>
     -+<RED>0123'4567<RESET><GREEN>0123'4560<RESET>
     ++0123'<RED>4567<RESET><GREEN>4560<RESET>
       // binary<RESET>
      -<RED>0b1000<RESET><GREEN>0b1100<RESET>+e1
     -+<RED>0b10'00<RESET><GREEN>0b11'00<RESET>+e1
     ++<RED>0b10<RESET><GREEN>0b11<RESET>'00+e1
       // expression<RESET>
       1.5-e+<RED>2<RESET><GREEN>3<RESET>+f
       // another one<RESET>
     +@@ t/t4034/cpp/expect: str.e+<RED>65<RESET><GREEN>75<RESET>
     + a<RED>*<RESET><GREEN>*=<RESET>b c<RED>/<RESET><GREEN>/=<RESET>d e<RED>%<RESET><GREEN>%=<RESET>f
     + a<RED>+<RESET><GREEN>++<RESET>b c<RED>-<RESET><GREEN>--<RESET>d
     + a<RED><<<RESET><GREEN><<=<RESET>b c<RED>>><RESET><GREEN>>>=<RESET>d
     +-a<RED><<RESET><GREEN><=<RESET>b c<RED><=<RESET><GREEN><<RESET>d e<RED>><RESET><GREEN>>=<RESET>f g<RED>>=<RESET><GREEN>><RESET>h
     ++a<RED><<RESET><GREEN><=<RESET>b c<RED><=<RESET><GREEN><<RESET>d e<RED>><RESET><GREEN>>=<RESET>f g<RED>>=<RESET><GREEN>><RESET>h i<=<GREEN>><RESET>j
     + a<RED>==<RESET><GREEN>!=<RESET>b c<RED>!=<RESET><GREEN>=<RESET>d
     + a<RED>^<RESET><GREEN>^=<RESET>b c<RED>|<RESET><GREEN>|=<RESET>d e<RED>&&<RESET><GREEN>&=<RESET>f
     + a<RED>||<RESET><GREEN>|<RESET>b
      
       ## t/t4034/cpp/post ##
     -@@ t/t4034/cpp/post: Foo() : x(0&42) { bar(x.Find); }
     +@@
     + Foo() : x(0&42) { bar(x.Find); }
       cout<<"Hello World?\n"<<endl;
     - (1 +1e10 0xabcdef) 'y'
     +-(1 +1e10 0xabcdef) 'y'
     ++(1 +1e10 0xabcdef) '.'
       // long double
      -3.141592654e+10l
      +3.141'592'654e+10l
     @@ t/t4034/cpp/post: Foo() : x(0&42) { bar(x.Find); }
       // expression
       1.5-e+3+f
       // another one
     +@@ t/t4034/cpp/post: str.e+75
     + a*=b c/=d e%=f
     + a++b c--d
     + a<<=b c>>=d
     +-a<=b c<d e>=f g>h
     ++a<=b c<d e>=f g>h i<=>j
     + a!=b c=d
     + a^=b c|=d e&=f
     + a|b
      
       ## t/t4034/cpp/pre ##
      @@ t/t4034/cpp/pre: Foo():x(0&&1){ foo0( x.find); }
     @@ t/t4034/cpp/pre: Foo():x(0&&1){ foo0( x.find); }
       // expression
       1.5-e+2+f
       // another one
     -
     - ## userdiff.c ##
     -@@ userdiff.c: PATTERNS("cpp",
     - 	 /* identifiers and keywords */
     - 	 "[a-zA-Z_][a-zA-Z0-9_]*"
     - 	 /* decimal and octal integers as well as floatingpoint numbers */
     --	 "|[0-9][0-9.]*([Ee][-+]?[0-9]+)?[fFlLuU]*"
     -+	 "|[0-9][0-9.']*([Ee][-+]?[0-9]+)?[fFlLuU]*"
     - 	 /* hexadecimal and binary integers */
     --	 "|0[xXbB][0-9a-fA-F]+[lLuU]*"
     -+	 "|0[xXbB][0-9a-fA-F']+[lLuU]*"
     - 	 /* floatingpoint numbers that begin with a decimal point */
     --	 "|\\.[0-9]+([Ee][-+]?[0-9]+)?[fFlL]?"
     -+	 "|\\.[0-9']+([Ee][-+]?[0-9]+)?[fFlL]?"
     - 	 "|[-+*/<>%&^|=!]=|--|\\+\\+|<<=?|>>=?|&&|\\|\\||::|->\\*?|\\.\\*"),
     - PATTERNS("csharp",
     - 	 /* Keywords */
     +@@ t/t4034/cpp/pre: str.e+65
     + a*b c/d e%f
     + a+b c-d
     + a<<b c>>d
     +-a<b c<=d e>f g>=h
     ++a<b c<=d e>f g>=h i<=j
     + a==b c!=d
     + a^b c|d e&&f
     + a||b
 -:  ----------- > 5:  037c743d9e3 userdiff-cpp: permit the digit-separating single-quote in numbers
 5:  43a701f5ffd ! 6:  cc9dc967f10 userdiff-cpp: learn the C++ spaceship operator
     @@ Commit message
          Signed-off-by: Johannes Sixt <j6t@kdbg.org>
      
       ## t/t4034/cpp/expect ##
     -@@
     - <BOLD>diff --git a/pre b/post<RESET>
     --<BOLD>index 60f3640..f6fbf7b 100644<RESET>
     -+<BOLD>index 144cd98..244f79c 100644<RESET>
     - <BOLD>--- a/pre<RESET>
     - <BOLD>+++ b/post<RESET>
     - <CYAN>@@ -1,30 +1,30 @@<RESET>
      @@ t/t4034/cpp/expect: str.e+<RED>65<RESET><GREEN>75<RESET>
       a<RED>*<RESET><GREEN>*=<RESET>b c<RED>/<RESET><GREEN>/=<RESET>d e<RED>%<RESET><GREEN>%=<RESET>f
       a<RED>+<RESET><GREEN>++<RESET>b c<RED>-<RESET><GREEN>--<RESET>d
       a<RED><<<RESET><GREEN><<=<RESET>b c<RED>>><RESET><GREEN>>>=<RESET>d
     --a<RED><<RESET><GREEN><=<RESET>b c<RED><=<RESET><GREEN><<RESET>d e<RED>><RESET><GREEN>>=<RESET>f g<RED>>=<RESET><GREEN>><RESET>h
     +-a<RED><<RESET><GREEN><=<RESET>b c<RED><=<RESET><GREEN><<RESET>d e<RED>><RESET><GREEN>>=<RESET>f g<RED>>=<RESET><GREEN>><RESET>h i<=<GREEN>><RESET>j
      +a<RED><<RESET><GREEN><=<RESET>b c<RED><=<RESET><GREEN><<RESET>d e<RED>><RESET><GREEN>>=<RESET>f g<RED>>=<RESET><GREEN>><RESET>h i<RED><=<RESET><GREEN><=><RESET>j
       a<RED>==<RESET><GREEN>!=<RESET>b c<RED>!=<RESET><GREEN>=<RESET>d
       a<RED>^<RESET><GREEN>^=<RESET>b c<RED>|<RESET><GREEN>|=<RESET>d e<RED>&&<RESET><GREEN>&=<RESET>f
       a<RED>||<RESET><GREEN>|<RESET>b
      
     - ## t/t4034/cpp/post ##
     -@@ t/t4034/cpp/post: str.e+75
     - a*=b c/=d e%=f
     - a++b c--d
     - a<<=b c>>=d
     --a<=b c<d e>=f g>h
     -+a<=b c<d e>=f g>h i<=>j
     - a!=b c=d
     - a^=b c|=d e&=f
     - a|b
     -
     - ## t/t4034/cpp/pre ##
     -@@ t/t4034/cpp/pre: str.e+65
     - a*b c/d e%f
     - a+b c-d
     - a<<b c>>d
     --a<b c<=d e>f g>=h
     -+a<b c<=d e>f g>=h i<=j
     - a==b c!=d
     - a^b c|d e&&f
     - a||b
     -
       ## userdiff.c ##
      @@ userdiff.c: PATTERNS("cpp",
       	 "|0[xXbB][0-9a-fA-F']+[lLuU]*"
       	 /* floatingpoint numbers that begin with a decimal point */
     - 	 "|\\.[0-9']+([Ee][-+]?[0-9]+)?[fFlL]?"
     + 	 "|\\.[0-9][0-9']*([Ee][-+]?[0-9]+)?[fFlL]?"
      -	 "|[-+*/<>%&^|=!]=|--|\\+\\+|<<=?|>>=?|&&|\\|\\||::|->\\*?|\\.\\*"),
      +	 "|[-+*/<>%&^|=!]=|--|\\+\\+|<<=?|>>=?|&&|\\|\\||::|->\\*?|\\.\\*|<=>"),
       PATTERNS("csharp",
-- 
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Message 17 of 24 in “Fun with cpp word regex”
  1. 0/3 Fun with cpp word regexJohannes Sixt via GitGitGadget, Oct 7, 2021
  2. 1/3 userdiff: tighten cpp word regexJohannes Sixt via GitGitGadget, Oct 7, 2021
  3. 2/3 userdiff: permit the digit-separating single-quote in numbersJohannes Sixt via GitGitGadget, Oct 7, 2021
  4. 3/3 userdiff: learn the C++ spaceship operatorJohannes Sixt via GitGitGadget, Oct 7, 2021
  5. Ævar Arnfjörð BjarmasonOct 7, 2021
  6. Johannes SixtOct 7, 2021
  7. 0/5 Fun with cpp word regexJohannes Sixt via GitGitGadget, Oct 8, 2021
  8. 1/5 t4034/cpp: actually test that operator tokens are not splitJohannes Sixt via GitGitGadget, Oct 8, 2021
  9. 2/5 t4034: add tests showing problematic cpp tokenizationsJohannes Sixt via GitGitGadget, Oct 8, 2021
  10. 3/5 userdiff-cpp: tighten word regexJohannes Sixt via GitGitGadget, Oct 8, 2021
  11. 4/5 userdiff-cpp: permit the digit-separating single-quote in numbersJohannes Sixt via GitGitGadget, Oct 8, 2021
  12. 5/5 userdiff-cpp: learn the C++ spaceship operatorJohannes Sixt via GitGitGadget, Oct 8, 2021
  13. Ævar Arnfjörð BjarmasonOct 8, 2021
  14. Johannes SixtOct 8, 2021
  15. Ævar Arnfjörð BjarmasonOct 9, 2021
  16. Johannes SixtOct 10, 2021
  17. 0/6 Fun with cpp word regexJohannes Sixt via GitGitGadget, Oct 10, 2021
  18. 1/6 t4034/cpp: actually test that operator tokens are not splitJohannes Sixt via GitGitGadget, Oct 10, 2021
  19. 2/6 t4034: add tests showing problematic cpp tokenizationsJohannes Sixt via GitGitGadget, Oct 10, 2021
  20. 4/6 userdiff-cpp: prepare test cases with yet unsupported featuresJohannes Sixt via GitGitGadget, Oct 10, 2021
  21. 3/6 userdiff-cpp: tighten word regexJohannes Sixt via GitGitGadget, Oct 10, 2021
  22. 5/6 userdiff-cpp: permit the digit-separating single-quote in numbersJohannes Sixt via GitGitGadget, Oct 10, 2021
  23. 6/6 userdiff-cpp: learn the C++ spaceship operatorJohannes Sixt via GitGitGadget, Oct 10, 2021
  24. 7/6 userdiff-cpp: back out the digit-separators in numbersJohannes Sixt, Oct 24, 2021

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