Re: read test snippet from stdin [was: [PATCH] t3900: add some more quotes]

[Jeff King]

On Thu, Jan 11, 2018 at 12:39:28PM +0100, SZEDER Gábor wrote:

> > diff --git a/t/t3900-i18n-commit.sh b/t/t3900-i18n-commit.sh
> > index 9e4e694d93..09ad4d8878 100755
> > --- a/t/t3900-i18n-commit.sh
> > +++ b/t/t3900-i18n-commit.sh
> > @@ -39,14 +39,14 @@ test_expect_success 'UTF-16 refused because of NULs' '
> > test_must_fail git commit -a -F "$TEST_DIRECTORY"/t3900/UTF-16.txt
> >  '
> >  
> > -test_expect_success 'UTF-8 invalid characters refused' '
> 
> Note that the test snippet started right after that last single quote,
> i.e. it started with a newline.
> 
> > -   test_when_finished "rm -f \"$HOME/stderr $HOME/invalid\"" &&
> > +test_expect_success 'UTF-8 invalid characters refused' - <<\EOT
> > +   test_when_finished 'rm -f "$HOME/stderr $HOME/invalid"' &&
> 
> And now it starts at the beginning of this line, i.e. without that
> leading neline.  This change leads to the following when run with '-v':

Yeah, I noticed that, too. It would be easy enough to add the extra
newline ourselves when printing the verbose output (quite a few of our
older tests don't start with a newline already, so it would be improving
them, too).

Alternatively, I considered adding a whole new helper function that
would skip the need to say "-" as the test body. And then it would
always know we were reading from the here-doc.

> > +   # command substitution eats trailing whitespace, so we add
> > +   # and then remove a non-whitespace character.
> > +   eval "$1=\$(cat; printf x)"
> > +   eval "$1=\${$1%x}"
> > +   fi
> > +}
> 
> Command substitutions don't eat trailing whitespaces in general, only
> trailing newlines.  POSIX:

Yeah, I wondered about that, but didn't bother digging since the
solution is the same either way.

> How about this alternative (also adding the missing leading newline
> mentioned above):
> 
> + eval "$1='
> +'\$(cat)'
> +'"
> 
> The indentation is yuck, but overall perhaps a bit less hacky...

I wrote something very similar at first, before finding the printf trick
on Stack Overflow. I thought the indentation on what I wrote was too
ugly. :)

I don't have a strong preference, and certainly if one is more portable
than the other, we should choose that.

The main point of my email was just to say "do people even like the
concept/direction?"

-Peff

read test snippet from stdin [was: [PATCH] t3900: add some more quotes]

[SZEDER Gábor]

> I've often wondered if
> our tests would be more readable taking the snippet over stdin.
> Something like:
> 
> diff --git a/t/t3900-i18n-commit.sh b/t/t3900-i18n-commit.sh
> index 9e4e694d93..09ad4d8878 100755
> --- a/t/t3900-i18n-commit.sh
> +++ b/t/t3900-i18n-commit.sh
> @@ -39,14 +39,14 @@ test_expect_success 'UTF-16 refused because of NULs' '
>   test_must_fail git commit -a -F "$TEST_DIRECTORY"/t3900/UTF-16.txt
>  '
>  
> -test_expect_success 'UTF-8 invalid characters refused' '

Note that the test snippet started right after that last single quote,
i.e. it started with a newline.

> - test_when_finished "rm -f \"$HOME/stderr $HOME/invalid\"" &&
> +test_expect_success 'UTF-8 invalid characters refused' - <<\EOT
> + test_when_finished 'rm -f "$HOME/stderr $HOME/invalid"' &&

And now it starts at the beginning of this line, i.e. without that
leading neline.  This change leads to the following when run with '-v':

  expecting success:test_when_finished 'rm -f "$HOME/stderr $HOME/invalid"' 
&&
echo "UTF-8 characters" >F &&
printf "Commit message\n\nInvalid surrogate:\355\240\200\n" \
>"$HOME/invalid" &&
git commit -a -F "$HOME/invalid" 2>"$HOME"/stderr &&
test_i18ngrep "did not conform" "$HOME"/stderr

Notice how the "expecting success" and the first line of the test ended
up in the same line.  I find this more annoying than the lack of empty
line between the colored and indented test code and the uncolored and
unindented test output.

>   echo "UTF-8 characters" >F &&
>   printf "Commit message\n\nInvalid surrogate:\355\240\200\n" \
>   >"$HOME/invalid" &&
>   git commit -a -F "$HOME/invalid" 2>"$HOME"/stderr &&
>   test_i18ngrep "did not conform" "$HOME"/stderr
> -'
> +EOT
>  
>  test_expect_success 'UTF-8 overlong sequences rejected' '
>   test_when_finished "rm -f \"$HOME/stderr $HOME/invalid\"" &&
> diff --git a/t/test-lib-functions.sh b/t/test-lib-functions.sh
> index 1701fe2a06..be8a47d304 100644
> --- a/t/test-lib-functions.sh
> +++ b/t/test-lib-functions.sh
> @@ -391,11 +391,32 @@ test_verify_prereq () {
>   error "bug in the test script: '$test_prereq' does not look like a 
> prereq"
>  }
>  
> +# Read from stdin into the variable given in $1.
> +test_read_to_eof () {
> + # Bash's "read" is sufficiently flexible that we can skip the extra
> + # process.
> + if test -n "$BASH_VERSION"
> + then
> + # 64k should be enough for anyone...
> + read -N 65536 -r "$1"
> + else
> + # command substitution eats trailing whitespace, so we add
> + # and then remove a non-whitespace character.
> + eval "$1=\$(cat; printf x)"
> + eval "$1=\${$1%x}"
> + fi
> +}

Command substitutions don't eat trailing whitespaces in general, only
trailing newlines.  POSIX:

  The shell shall expand the command substitution by executing command
  in a subshell environment (see Shell Execution Environment) and
  replacing the command substitution (the text of command plus the
  enclosing "$()" or backquotes) with the standard output of the
  command, removing sequences of one or more s at the end of
  the substitution.

Bash and dash conform to this.

How about this alternative (also adding the missing leading newline
mentioned above):

+   eval "$1='
+'\$(cat)'
+'"

The indentation is yuck, but overall perhaps a bit less hacky...

Re: [PATCH] t3900: add some more quotes

[Jeff King]

On Wed, Jan 10, 2018 at 01:31:22PM -0800, Junio C Hamano wrote:

> > +# Read from stdin into the variable given in $1.
> > +test_read_to_eof () {
> > +   # Bash's "read" is sufficiently flexible that we can skip the extra
> > +   # process.
> > +   if test -n "$BASH_VERSION"
> > +   then
> > +   # 64k should be enough for anyone...
> > +   read -N 65536 -r "$1"
> > +   else
> > +   # command substitution eats trailing whitespace, so we add
> > +   # and then remove a non-whitespace character.
> > +   eval "$1=\$(cat; printf x)"
> > +   eval "$1=\${$1%x}"
> > +   fi
> > +}
> 
> Yuck.  Hacky but nice.
> 
> I think this will make it easier to read but I suspect here text
> would use temporary files and may slow things down a bit?  I do not
> know if it is even measurable, though.

Yeah, since I was able to contain the horrible-ness in this function, I
think the overall readability/portability is probably OK. My main
concern was that it would be slower (hence the bash hackery). I applied
the patch below on top to see what kind of impact we could measure
across the whole suite:

diff --git a/t/test-lib-functions.sh b/t/test-lib-functions.sh
index be8a47d304..6f2e6e7560 100644
--- a/t/test-lib-functions.sh
+++ b/t/test-lib-functions.sh
@@ -441,6 +441,15 @@ test_expect_success () {
then
test_read_to_eof test_block
set -- "$1" "$test_block"
+   else
+   # this is obviously a dumb thing to do, but it's just
+   # a performance-testing hack.
+   test_read_to_eof test_block <

Re: [PATCH] t3900: add some more quotes

[Junio C Hamano]

Jeff King  writes:

> Yeah. One of the reasons for both of the errors in this thread is the
> nested double-quoting. Using single quotes is awkward because we're
> already using them to delimit the whole snippet.  I've often wondered if
> our tests would be more readable taking the snippet over stdin.
> Something like:
> +test_expect_success 'UTF-8 invalid characters refused' - <<\EOT
> + test_when_finished 'rm -f "$HOME/stderr $HOME/invalid"' &&
> ...
> -'
> +EOT
> 
> +# Read from stdin into the variable given in $1.
> +test_read_to_eof () {
> + # Bash's "read" is sufficiently flexible that we can skip the extra
> + # process.
> + if test -n "$BASH_VERSION"
> + then
> + # 64k should be enough for anyone...
> + read -N 65536 -r "$1"
> + else
> + # command substitution eats trailing whitespace, so we add
> + # and then remove a non-whitespace character.
> + eval "$1=\$(cat; printf x)"
> + eval "$1=\${$1%x}"
> + fi
> +}

Yuck.  Hacky but nice.

I think this will make it easier to read but I suspect here text
would use temporary files and may slow things down a bit?  I do not
know if it is even measurable, though.

> +
>  test_expect_failure () {
>   test_start_
>   test "$#" = 3 && { test_prereq=$1; shift; } || test_prereq=
>   test "$#" = 2 ||
>   error "bug in the test script: not 2 or 3 parameters to 
> test-expect-failure"
> + if test "$2" = "-"
> + then
> + test_read_to_eof test_block
> + set -- "$1" "$test_block"
> + fi
>   test_verify_prereq
>   export test_prereq
>   if ! test_skip "$@"
> @@ -416,6 +437,11 @@ test_expect_success () {
>   test "$#" = 3 && { test_prereq=$1; shift; } || test_prereq=
>   test "$#" = 2 ||
>   error "bug in the test script: not 2 or 3 parameters to 
> test-expect-success"
> + if test "$2" = "-"
> + then
> + test_read_to_eof test_block
> + set -- "$1" "$test_block"
> + fi
>   test_verify_prereq
>   export test_prereq
>   if ! test_skip "$@"

Re: [PATCH] t3900: add some more quotes

[Jeff King]

On Wed, Jan 10, 2018 at 08:02:09PM +0100, Johannes Sixt wrote:

> > diff --git a/t/t3900-i18n-commit.sh b/t/t3900-i18n-commit.sh
> > index 9e4e694d9..dc00db87b 100755
> > --- a/t/t3900-i18n-commit.sh
> > +++ b/t/t3900-i18n-commit.sh
> > @@ -40,7 +40,7 @@ test_expect_success 'UTF-16 refused because of NULs' '
> >   '
> >   test_expect_success 'UTF-8 invalid characters refused' '
> > -   test_when_finished "rm -f \"$HOME/stderr $HOME/invalid\"" &&
> > +   test_when_finished "rm -f \"$HOME/stderr\" \"$HOME/invalid\"" &&
> 
> Should that not better be
> 
>   test_when_finished "rm -f \"\$HOME/stderr\" \"\$HOME/invalid\""
> 
> i.e., delay the expansion of $HOME to protect against double-quotes in the
> path?

Yeah. One of the reasons for both of the errors in this thread is the
nested double-quoting. Using single quotes is awkward because we're
already using them to delimit the whole snippet.  I've often wondered if
our tests would be more readable taking the snippet over stdin.
Something like:

diff --git a/t/t3900-i18n-commit.sh b/t/t3900-i18n-commit.sh
index 9e4e694d93..09ad4d8878 100755
--- a/t/t3900-i18n-commit.sh
+++ b/t/t3900-i18n-commit.sh
@@ -39,14 +39,14 @@ test_expect_success 'UTF-16 refused because of NULs' '
test_must_fail git commit -a -F "$TEST_DIRECTORY"/t3900/UTF-16.txt
 '
 
-test_expect_success 'UTF-8 invalid characters refused' '
-   test_when_finished "rm -f \"$HOME/stderr $HOME/invalid\"" &&
+test_expect_success 'UTF-8 invalid characters refused' - <<\EOT
+   test_when_finished 'rm -f "$HOME/stderr $HOME/invalid"' &&
echo "UTF-8 characters" >F &&
printf "Commit message\n\nInvalid surrogate:\355\240\200\n" \
>"$HOME/invalid" &&
git commit -a -F "$HOME/invalid" 2>"$HOME"/stderr &&
test_i18ngrep "did not conform" "$HOME"/stderr
-'
+EOT
 
 test_expect_success 'UTF-8 overlong sequences rejected' '
test_when_finished "rm -f \"$HOME/stderr $HOME/invalid\"" &&
diff --git a/t/test-lib-functions.sh b/t/test-lib-functions.sh
index 1701fe2a06..be8a47d304 100644
--- a/t/test-lib-functions.sh
+++ b/t/test-lib-functions.sh
@@ -391,11 +391,32 @@ test_verify_prereq () {
error "bug in the test script: '$test_prereq' does not look like a 
prereq"
 }
 
+# Read from stdin into the variable given in $1.
+test_read_to_eof () {
+   # Bash's "read" is sufficiently flexible that we can skip the extra
+   # process.
+   if test -n "$BASH_VERSION"
+   then
+   # 64k should be enough for anyone...
+   read -N 65536 -r "$1"
+   else
+   # command substitution eats trailing whitespace, so we add
+   # and then remove a non-whitespace character.
+   eval "$1=\$(cat; printf x)"
+   eval "$1=\${$1%x}"
+   fi
+}
+
 test_expect_failure () {
test_start_
test "$#" = 3 && { test_prereq=$1; shift; } || test_prereq=
test "$#" = 2 ||
error "bug in the test script: not 2 or 3 parameters to 
test-expect-failure"
+   if test "$2" = "-"
+   then
+   test_read_to_eof test_block
+   set -- "$1" "$test_block"
+   fi
test_verify_prereq
export test_prereq
if ! test_skip "$@"
@@ -416,6 +437,11 @@ test_expect_success () {
test "$#" = 3 && { test_prereq=$1; shift; } || test_prereq=
test "$#" = 2 ||
error "bug in the test script: not 2 or 3 parameters to 
test-expect-success"
+   if test "$2" = "-"
+   then
+   test_read_to_eof test_block
+   set -- "$1" "$test_block"
+   fi
test_verify_prereq
export test_prereq
if ! test_skip "$@"

Re: [PATCH] t3900: add some more quotes

[Junio C Hamano]

Johannes Sixt  writes:

>> test_expect_success 'UTF-8 invalid characters refused' '
>> -test_when_finished "rm -f \"$HOME/stderr $HOME/invalid\"" &&
>> +test_when_finished "rm -f \"$HOME/stderr\" \"$HOME/invalid\"" &&
>
> Should that not better be
>
>   test_when_finished "rm -f \"\$HOME/stderr\" \"\$HOME/invalid\""
>
> i.e., delay the expansion of $HOME to protect against double-quotes in
> the path?

Yes ;-)

Re: [PATCH] t3900: add some more quotes

[Johannes Sixt]

Am 10.01.2018 um 10:58 schrieb Beat Bolli:

In 89a70b80 ("t0302 & t3900: add forgotten quotes", 2018-01-03), quotes
were added to protect against spaces in $HOME. In the test_when_finished
hander, two files are deleted which must be quoted individually.

Signed-off-by: Beat Bolli 
---
  t/t3900-i18n-commit.sh | 8 
  1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/t/t3900-i18n-commit.sh b/t/t3900-i18n-commit.sh
index 9e4e694d9..dc00db87b 100755
--- a/t/t3900-i18n-commit.sh
+++ b/t/t3900-i18n-commit.sh
@@ -40,7 +40,7 @@ test_expect_success 'UTF-16 refused because of NULs' '
  '
  
  test_expect_success 'UTF-8 invalid characters refused' '

-   test_when_finished "rm -f \"$HOME/stderr $HOME/invalid\"" &&
+   test_when_finished "rm -f \"$HOME/stderr\" \"$HOME/invalid\"" &&


Should that not better be

test_when_finished "rm -f \"\$HOME/stderr\" \"\$HOME/invalid\""

i.e., delay the expansion of $HOME to protect against double-quotes in 
the path?


-- Hannes

Re: [PATCH] t3900: add some more quotes

[Eric Sunshine]

On Wed, Jan 10, 2018 at 4:58 AM, Beat Bolli  wrote:
> In 89a70b80 ("t0302 & t3900: add forgotten quotes", 2018-01-03), quotes
> were added to protect against spaces in $HOME. In the test_when_finished
> hander, two files are deleted which must be quoted individually.

s/hander/handler/

> Signed-off-by: Beat Bolli 

Re: [PATCH] t3900: add some more quotes

[Johannes Schindelin]

Hi,

On Wed, 10 Jan 2018, Jeff King wrote:

> On Wed, Jan 10, 2018 at 10:58:32AM +0100, Beat Bolli wrote:
> 
> > In 89a70b80 ("t0302 & t3900: add forgotten quotes", 2018-01-03), quotes
> > were added to protect against spaces in $HOME. In the test_when_finished
> > hander, two files are deleted which must be quoted individually.
> 
> Doh. I can't believe I missed that when reading the patch.

D'oh, and I can't believe that I missed this when writing the patch.

Thanks, Beat!
Dscho

Re: [PATCH] t3900: add some more quotes

[Jeff King]

On Wed, Jan 10, 2018 at 10:58:32AM +0100, Beat Bolli wrote:

> In 89a70b80 ("t0302 & t3900: add forgotten quotes", 2018-01-03), quotes
> were added to protect against spaces in $HOME. In the test_when_finished
> hander, two files are deleted which must be quoted individually.

Doh. I can't believe I missed that when reading the patch.

Thanks.

-Peff

[PATCH] t3900: add some more quotes

[Beat Bolli]

In 89a70b80 ("t0302 & t3900: add forgotten quotes", 2018-01-03), quotes
were added to protect against spaces in $HOME. In the test_when_finished
hander, two files are deleted which must be quoted individually.

Signed-off-by: Beat Bolli 
---
 t/t3900-i18n-commit.sh | 8 
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/t/t3900-i18n-commit.sh b/t/t3900-i18n-commit.sh
index 9e4e694d9..dc00db87b 100755
--- a/t/t3900-i18n-commit.sh
+++ b/t/t3900-i18n-commit.sh
@@ -40,7 +40,7 @@ test_expect_success 'UTF-16 refused because of NULs' '
 '
 
 test_expect_success 'UTF-8 invalid characters refused' '
-   test_when_finished "rm -f \"$HOME/stderr $HOME/invalid\"" &&
+   test_when_finished "rm -f \"$HOME/stderr\" \"$HOME/invalid\"" &&
echo "UTF-8 characters" >F &&
printf "Commit message\n\nInvalid surrogate:\355\240\200\n" \
>"$HOME/invalid" &&
@@ -49,7 +49,7 @@ test_expect_success 'UTF-8 invalid characters refused' '
 '
 
 test_expect_success 'UTF-8 overlong sequences rejected' '
-   test_when_finished "rm -f \"$HOME/stderr $HOME/invalid\"" &&
+   test_when_finished "rm -f \"$HOME/stderr\" \"$HOME/invalid\"" &&
rm -f "$HOME/stderr" "$HOME/invalid" &&
echo "UTF-8 overlong" >F &&
printf "\340\202\251ommit message\n\nThis is not a space:\300\240\n" \
@@ -59,7 +59,7 @@ test_expect_success 'UTF-8 overlong sequences rejected' '
 '
 
 test_expect_success 'UTF-8 non-characters refused' '
-   test_when_finished "rm -f \"$HOME/stderr $HOME/invalid\"" &&
+   test_when_finished "rm -f \"$HOME/stderr\" \"$HOME/invalid\"" &&
echo "UTF-8 non-character 1" >F &&
printf "Commit message\n\nNon-character:\364\217\277\276\n" \
>"$HOME/invalid" &&
@@ -68,7 +68,7 @@ test_expect_success 'UTF-8 non-characters refused' '
 '
 
 test_expect_success 'UTF-8 non-characters refused' '
-   test_when_finished "rm -f \"$HOME/stderr $HOME/invalid\"" &&
+   test_when_finished "rm -f \"$HOME/stderr\" \"$HOME/invalid\"" &&
echo "UTF-8 non-character 2." >F &&
printf "Commit message\n\nNon-character:\357\267\220\n" \
>"$HOME/invalid" &&
-- 
2.15.0.rc1.299.gda03b47c3