[PATCH v4 0/6] convert: add support for different encodings

[lars.schneider@autodesk.com]

From: Lars Schneider <larsxschneider@gmail.com>

Hi,

Patches 1-4 and 6 are preparation and helper functions.
Patch 5 is the actual change.

This series depends on Torsten's "convert_to_git(): safe_crlf/checksafe
becomes int conv_flags" patch:
https://public-inbox.org/git/20180113224931.27031-1-tboegi@web.de/

Changes since v3:

* I renamed the attribute from "checkout-encoding" to "working-tree-encoding"
  in the hope to convey better what the attribute is about.

* I rebased the series to Git 2.16 and removed Torsten's patch as he
  posted the patch on his own.

* Fix documentation wording. (Torsten)

* A macro was used in a commit before it's introduction. Fixed!(Junio)

Thanks,
Lars

   RFC: https://public-inbox.org/git/BDB9B884-6D17-4BE3-A83C-F67E2AFA2B46@gmail.com/
    v1: https://public-inbox.org/git/20171211155023.1405-1-lars.schneider@autodesk.com/
    v2: https://public-inbox.org/git/20171229152222.39680-1-lars.schneider@autodesk.com/
    v3: https://public-inbox.org/git/20180106004808.77513-1-lars.schneider@autodesk.com/


Base Ref:
Web-Diff: https://github.com/larsxschneider/git/commit/21f4dac5ab
Checkout: git fetch https://github.com/larsxschneider/git encoding-v4 && git checkout 21f4dac5ab


### Interdiff (v3-rebased-2.16..v4):

diff --git a/Documentation/gitattributes.txt b/Documentation/gitattributes.txt
index 1bc03e69cb..a8dbf4be30 100644
--- a/Documentation/gitattributes.txt
+++ b/Documentation/gitattributes.txt
@@ -272,8 +272,8 @@ few exceptions.  Even though...
   catch potential problems early, safety triggers.


-`checkout-encoding`
-^^^^^^^^^^^^^^^^^^^
+`working-tree-encoding`
+^^^^^^^^^^^^^^^^^^^^^^^

 Git recognizes files encoded with ASCII or one of its supersets (e.g.
 UTF-8 or ISO-8859-1) as text files.  All other encodings are usually
@@ -281,17 +281,17 @@ interpreted as binary and consequently built-in Git text processing
 tools (e.g. 'git diff') as well as most Git web front ends do not
 visualize the content.

-In these cases you can teach Git the encoding of a file in the working
-directory with the `checkout-encoding` attribute. If a file with this
+In these cases you can tell Git the encoding of a file in the working
+directory with the `working-tree-encoding` attribute. If a file with this
 attributes is added to Git, then Git reencodes the content from the
 specified encoding to UTF-8 and stores the result in its internal data
 structure (called "the index"). On checkout the content is encoded
 back to the specified encoding.

-Please note that using the `checkout-encoding` attribute may have a
+Please note that using the `working-tree-encoding` attribute may have a
 number of pitfalls:

-- Git clients that do not support the `checkout-encoding` attribute
+- Git clients that do not support the `working-tree-encoding` attribute
   will checkout the respective files UTF-8 encoded and not in the
   expected encoding. Consequently, these files will appear different
   which typically causes trouble. This is in particular the case for
@@ -304,7 +304,7 @@ number of pitfalls:
 - Reencoding content requires resources that might slow down certain
   Git operations (e.g 'git checkout' or 'git add').

-Use the `checkout-encoding` attribute only if you cannot store a file in
+Use the `working-tree-encoding` attribute only if you cannot store a file in
 UTF-8 encoding and if you want Git to be able to process the content as
 text.

@@ -313,7 +313,7 @@ with byte order mark (BOM) and you want Git to perform automatic line
 ending conversion based on your platform.

 ------------------------
-*.txt    text checkout-encoding=UTF-16
+*.txt    text working-tree-encoding=UTF-16
 ------------------------

 Use the following attributes if your '*.txt' files are UTF-16 little
@@ -321,7 +321,7 @@ endian encoded without BOM and you want Git to use Windows line endings
 in the working directory.

 ------------------------
-*.txt    checkout-encoding=UTF-16LE text eol=CRLF
+*.txt    working-tree-encoding=UTF-16LE text eol=CRLF
 ------------------------

 You can get a list of all available encodings on your platform with the
diff --git a/convert.c b/convert.c
index 8559651b3f..13fad490ce 100644
--- a/convert.c
+++ b/convert.c
@@ -323,7 +323,7 @@ static int encode_to_git(const char *path, const char *src, size_t src_len,
    const char *advise_msg = _(
      "You told Git to treat '%s' as %s. A byte order mark "
      "(BOM) is prohibited with this encoding. Either use "
-     "%.6s as checkout encoding or remove the BOM from the "
+     "%.6s as working tree encoding or remove the BOM from the "
      "file.");

    advise(advise_msg, path, enc->name, enc->name, enc->name);
@@ -339,7 +339,7 @@ static int encode_to_git(const char *path, const char *src, size_t src_len,
    const char *advise_msg = _(
      "You told Git to treat '%s' as %s. A byte order mark "
      "(BOM) is required with this encoding. Either use "
-     "%sBE/%sLE as checkout encoding or add a BOM to the "
+     "%sBE/%sLE as working tree encoding or add a BOM to the "
      "file.");
    advise(advise_msg, path, enc->name, enc->name, enc->name);
    if (conv_flags & CONV_WRITE_OBJECT)
@@ -1237,7 +1237,7 @@ static void convert_attrs(struct conv_attrs *ca, const char *path)

  if (!check) {
    check = attr_check_initl("crlf", "ident", "filter",
-          "eol", "text", "checkout-encoding",
+          "eol", "text", "working-tree-encoding",
           NULL);
    user_convert_tail = &user_convert;
    encoding_tail = &encoding;
diff --git a/t/t0028-checkout-encoding.sh b/t/t0028-working-tree-encoding.sh
similarity index 89%
rename from t/t0028-checkout-encoding.sh
rename to t/t0028-working-tree-encoding.sh
index 5f1c911c07..0f36d4990a 100755
--- a/t/t0028-checkout-encoding.sh
+++ b/t/t0028-working-tree-encoding.sh
@@ -1,6 +1,6 @@
 #!/bin/sh

-test_description='checkout-encoding conversion via gitattributes'
+test_description='working-tree-encoding conversion via gitattributes'

 . ./test-lib.sh

@@ -10,7 +10,7 @@ test_expect_success 'setup test repo' '
  git config core.eol lf &&

  text="hallo there!\ncan you read me?" &&
- echo "*.utf16 text checkout-encoding=utf-16" >.gitattributes &&
+ echo "*.utf16 text working-tree-encoding=utf-16" >.gitattributes &&
  printf "$text" >test.utf8.raw &&
  printf "$text" | iconv -f UTF-8 -t UTF-16 >test.utf16.raw &&
  cp test.utf16.raw test.utf16 &&
@@ -45,10 +45,10 @@ test_expect_success 'check prohibited UTF BOM' '
  printf "\0\0\376\777\0\0\0a\0\0\0b\0\0\0c" >bebom.utf32be.raw &&
  printf "\777\376\0\0a\0\0\0b\0\0\0c\0\0\0" >lebom.utf32le.raw &&

- echo "*.utf16be text checkout-encoding=utf-16be" >>.gitattributes &&
- echo "*.utf16le text checkout-encoding=utf-16le" >>.gitattributes &&
- echo "*.utf32be text checkout-encoding=utf-32be" >>.gitattributes &&
- echo "*.utf32le text checkout-encoding=utf-32le" >>.gitattributes &&
+ echo "*.utf16be text working-tree-encoding=utf-16be" >>.gitattributes &&
+ echo "*.utf16le text working-tree-encoding=utf-16le" >>.gitattributes &&
+ echo "*.utf32be text working-tree-encoding=utf-32be" >>.gitattributes &&
+ echo "*.utf32le text working-tree-encoding=utf-32le" >>.gitattributes &&

  # Here we add a UTF-16 files with BOM (big-endian and little-endian)
  # but we tell Git to treat it as UTF-16BE/UTF-16LE. In these cases
@@ -91,7 +91,7 @@ test_expect_success 'check prohibited UTF BOM' '
 '

 test_expect_success 'check required UTF BOM' '
- echo "*.utf32 text checkout-encoding=utf-32" >>.gitattributes &&
+ echo "*.utf32 text working-tree-encoding=utf-32" >>.gitattributes &&

  cp nobom.utf16be.raw nobom.utf16 &&
  test_must_fail git add nobom.utf16 2>err.out &&
@@ -143,11 +143,11 @@ test_expect_success 'eol conversion for UTF-16 encoded files on checkout' '

 test_expect_success 'check unsupported encodings' '

- echo "*.nothing text checkout-encoding=" >>.gitattributes &&
+ echo "*.nothing text working-tree-encoding=" >>.gitattributes &&
  printf "nothing" >t.nothing &&
  git add t.nothing &&

- echo "*.garbage text checkout-encoding=garbage" >>.gitattributes &&
+ echo "*.garbage text working-tree-encoding=garbage" >>.gitattributes &&
  printf "garbage" >t.garbage &&
  test_must_fail git add t.garbage 2>err.out &&
  test_i18ngrep "fatal: failed to encode" err.out &&
@@ -161,7 +161,7 @@ test_expect_success 'error if encoding round trip is not the same during refresh
  BEFORE_STATE=$(git rev-parse HEAD) &&

  # Skip the UTF-16 filter for the added file
- # This simulates a Git version that has no checkoutEncoding support
+ # This simulates a Git version that has no working tree encoding support
  echo "hallo" >nonsense.utf16 &&
  TEST_HASH=$(git hash-object --no-filters -w nonsense.utf16) &&
  git update-index --add --cacheinfo 100644 $TEST_HASH nonsense.utf16 &&



### Patches

Lars Schneider (6):
  strbuf: remove unnecessary NUL assignment in xstrdup_tolower()
  strbuf: add xstrdup_toupper()
  utf8: add function to detect prohibited UTF-16/32 BOM
  utf8: add function to detect a missing UTF-16/32 BOM
  convert: add 'working-tree-encoding' attribute
  convert: add tracing for 'working-tree-encoding' attribute

 Documentation/gitattributes.txt  |  60 +++++++++++
 convert.c                        | 218 ++++++++++++++++++++++++++++++++++++++-
 convert.h                        |   1 +
 sha1_file.c                      |   2 +-
 strbuf.c                         |  13 ++-
 strbuf.h                         |   1 +
 t/t0028-working-tree-encoding.sh | 198 +++++++++++++++++++++++++++++++++++
 utf8.c                           |  37 +++++++
 utf8.h                           |  25 +++++
 9 files changed, 552 insertions(+), 3 deletions(-)
 create mode 100755 t/t0028-working-tree-encoding.sh


base-commit: 8a2f0888555ce46ac87452b194dec5cb66fb1417
--
2.16.0