Change detection method for checking package name changes

Change detection method for checking package name changes

The return status of apt-cache show doesn't actually indicate whether a package has any candidates, so we now call grep on apt-cache pkgnames to determine this.

BUG=244473
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=203000

[solb, 2013-05-23 17:33:00]

This patch was necessary before I was able to install the build dependencies on
my precise Goobuntu system.

[Lambros, 2013-05-28 18:26:58]

Paweł, could you take a look please as well?

https://codereview.chromium.org/15741015/diff/1/build/install-build-deps.sh
File build/install-build-deps.sh (right):

https://codereview.chromium.org/15741015/diff/1/build/install-build-deps.sh#n...
build/install-build-deps.sh:127: | grep "Candidate: (none)" >/dev/null 2>&1 );
then
I don't know if this will work for non-English locales.

Have a look in /etc/bash-completion.d/apt and see how they test for available
package names. For example, the apt-cache "pkgnames" option looks promising.

Also, consider encapsulating the test into a Bash function, instead of repeating
the code 5 times.

[solb, 2013-05-28 18:41:48]

On 2013/05/28 18:26:58, Lambros wrote:
> Paweł, could you take a look please as well?
> 
> https://codereview.chromium.org/15741015/diff/1/build/install-build-deps.sh
> File build/install-build-deps.sh (right):
> 
>
https://codereview.chromium.org/15741015/diff/1/build/install-build-deps.sh#n...
> build/install-build-deps.sh:127: | grep "Candidate: (none)" >/dev/null 2>&1 );
> then
> I don't know if this will work for non-English locales.
> 
> Have a look in /etc/bash-completion.d/apt and see how they test for available
> package names. For example, the apt-cache "pkgnames" option looks promising.
> 
> Also, consider encapsulating the test into a Bash function, instead of
repeating
> the code 5 times.

Good point, and thanks for suggesting Bash completion.  It looks like they use
something like:
$ apt-cache --no-generate pkgnames | grep -x $pkgname

[solb, 2013-05-28 18:55:37]

On 2013/05/28 18:41:48, solb wrote:
> On 2013/05/28 18:26:58, Lambros wrote:
> > Paweł, could you take a look please as well?
> > 
> > https://codereview.chromium.org/15741015/diff/1/build/install-build-deps.sh
> > File build/install-build-deps.sh (right):
> > 
> >
>
https://codereview.chromium.org/15741015/diff/1/build/install-build-deps.sh#n...
> > build/install-build-deps.sh:127: | grep "Candidate: (none)" >/dev/null 2>&1
);
> > then
> > I don't know if this will work for non-English locales.
> > 
> > Have a look in /etc/bash-completion.d/apt and see how they test for
available
> > package names. For example, the apt-cache "pkgnames" option looks promising.
> > 
> > Also, consider encapsulating the test into a Bash function, instead of
> repeating
> > the code 5 times.
> 
> Good point, and thanks for suggesting Bash completion.  It looks like they use
> something like:
> $ apt-cache --no-generate pkgnames | grep -x $pkgname

I updated the script to use the aforementioned mechanism instead.

[Paweł Hajdan Jr., 2013-05-28 19:06:27]

Also note following change: https://chromiumcodereview.appspot.com/15911004

https://codereview.chromium.org/15741015/diff/6001/build/install-build-deps.sh
File build/install-build-deps.sh (right):

https://codereview.chromium.org/15741015/diff/6001/build/install-build-deps.s...
build/install-build-deps.sh:26: satisfiable() {
nit: Let's change the name from very generic to one of (more suggestions
welcome):

- is_package_dependency_satisfiable
- has_package
- is_package_installable
- is_package_available
- package_exists

https://codereview.chromium.org/15741015/diff/6001/build/install-build-deps.s...
build/install-build-deps.sh:27: apt-cache --no-generate pkgnames | grep -x $1 >
/dev/null 2>&1
Why --no-generate? Just asking for better understanding, and possibly worth a
comment.

[Lambros, 2013-05-28 19:09:54]

Looks fine, but I'll defer to Pawel for final LG.

https://codereview.chromium.org/15741015/diff/6001/build/install-build-deps.sh
File build/install-build-deps.sh (right):

https://codereview.chromium.org/15741015/diff/6001/build/install-build-deps.s...
build/install-build-deps.sh:26: satisfiable() {
On 2013/05/28 19:06:27, Paweł Hajdan Jr. wrote:
> nit: Let's change the name from very generic to one of (more suggestions
> welcome):
+1 on renaming

https://codereview.chromium.org/15741015/diff/6001/build/install-build-deps.s...
build/install-build-deps.sh:27: apt-cache --no-generate pkgnames | grep -x $1 >
/dev/null 2>&1
style nit: "$1". We prefer to quote variables, even though it makes no
difference in this case.

[solb, 2013-05-28 20:20:33]

On 2013/05/28 19:09:54, Lambros wrote:
> Looks fine, but I'll defer to Pawel for final LG.
> 
> https://codereview.chromium.org/15741015/diff/6001/build/install-build-deps.sh
> File build/install-build-deps.sh (right):
> 
>
https://codereview.chromium.org/15741015/diff/6001/build/install-build-deps.s...
> build/install-build-deps.sh:26: satisfiable() {
> On 2013/05/28 19:06:27, Paweł Hajdan Jr. wrote:
> > nit: Let's change the name from very generic to one of (more suggestions
> > welcome):
> +1 on renaming
> 
>
https://codereview.chromium.org/15741015/diff/6001/build/install-build-deps.s...
> build/install-build-deps.sh:27: apt-cache --no-generate pkgnames | grep -x $1
>
> /dev/null 2>&1
> style nit: "$1". We prefer to quote variables, even though it makes no
> difference in this case.

I made the requested name/style changes and removed the --no-generate flag.  (I
originally included the latter because it was used by bash-completion to speed
up execution of the command; however, time confirms that the difference is on
the order of magnitude of 0.01 s for subsequent executions after the cache has
already been regenerated once.)

[solb, 2013-05-28 21:02:06]

On 2013/05/28 20:20:33, solb wrote:
> On 2013/05/28 19:09:54, Lambros wrote:
> > Looks fine, but I'll defer to Pawel for final LG.
> > 
> >
https://codereview.chromium.org/15741015/diff/6001/build/install-build-deps.sh
> > File build/install-build-deps.sh (right):
> > 
> >
>
https://codereview.chromium.org/15741015/diff/6001/build/install-build-deps.s...
> > build/install-build-deps.sh:26: satisfiable() {
> > On 2013/05/28 19:06:27, Paweł Hajdan Jr. wrote:
> > > nit: Let's change the name from very generic to one of (more suggestions
> > > welcome):
> > +1 on renaming
> > 
> >
>
https://codereview.chromium.org/15741015/diff/6001/build/install-build-deps.s...
> > build/install-build-deps.sh:27: apt-cache --no-generate pkgnames | grep -x
$1
> >
> > /dev/null 2>&1
> > style nit: "$1". We prefer to quote variables, even though it makes no
> > difference in this case.
> 
> I made the requested name/style changes and removed the --no-generate flag. 
(I
> originally included the latter because it was used by bash-completion to speed
> up execution of the command; however, time confirms that the difference is on
> the order of magnitude of 0.01 s for subsequent executions after the cache has
> already been regenerated once.)

I rebased this against upstream; if it looks okay, could someone commit it for
me?

[Lambros, 2013-05-29 17:33:41]

On 2013/05/28 21:02:06, solb wrote:
> On 2013/05/28 20:20:33, solb wrote:
> > On 2013/05/28 19:09:54, Lambros wrote:
> > > Looks fine, but I'll defer to Pawel for final LG.
> > > 
> > >
> https://codereview.chromium.org/15741015/diff/6001/build/install-build-deps.sh
> > > File build/install-build-deps.sh (right):
> > > 
> > >
> >
>
https://codereview.chromium.org/15741015/diff/6001/build/install-build-deps.s...
> > > build/install-build-deps.sh:26: satisfiable() {
> > > On 2013/05/28 19:06:27, Paweł Hajdan Jr. wrote:
> > > > nit: Let's change the name from very generic to one of (more suggestions
> > > > welcome):
> > > +1 on renaming
> > > 
> > >
> >
>
https://codereview.chromium.org/15741015/diff/6001/build/install-build-deps.s...
> > > build/install-build-deps.sh:27: apt-cache --no-generate pkgnames | grep -x
> $1
> > >
> > > /dev/null 2>&1
> > > style nit: "$1". We prefer to quote variables, even though it makes no
> > > difference in this case.
> > 
> > I made the requested name/style changes and removed the --no-generate flag. 
> (I
> > originally included the latter because it was used by bash-completion to
speed
> > up execution of the command; however, time confirms that the difference is
on
> > the order of magnitude of 0.01 s for subsequent executions after the cache
has
> > already been regenerated once.)
> 
> I rebased this against upstream; if it looks okay, could someone commit it for
> me?

Pawel, any objection to landing this?

[Paweł Hajdan Jr., 2013-05-29 19:13:47]

LGTM

[commit-bot: I haz the power, 2013-05-29 19:47:11]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/solb@chromium.org/15741015/14001

[commit-bot: I haz the power, 2013-05-29 19:50:33]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/solb@chromium.org/15741015/14001

[commit-bot: I haz the power, 2013-05-29 23:11:21]

Change committed as 203000