run-tests: collect aggregate code coverage
Before this patch, every Python process during a code coverage run was
writing coverage data to the same file. I'm not sure if the coverage
package even tries to obtain a lock on the file. But what I do know is
there was some last write wins leading to loss of code coverage data, at
least with -j > 1.
This patch changes the code coverage mechanism to be multiple process
safe. The mechanism for initializing code coverage via sitecustomize.py
has been tweaked so each Python process will produce a separate coverage
data file on disk. Unless two processes generate the same random value,
there are no race conditions writing to the same file. At the end of the
test run, we combine all written files into an aggregate report.
On my machine, running the full test suite produces a little over
20,000 coverage files consuming ~350 MB. As you can imagine, it takes
several seconds to load and merge these coverage files. But when it is
done, you have an accurate picture of the aggregate code coverage for the
entire test suite, which is ~60% line coverage.
$ hg init t
$ cd t
$ mkdir a
$ echo foo > a/a
$ echo bar > a/b
$ hg ci -Am "0"
adding a/a
adding a/b
$ hg co -C 0
0 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg mv a b
moving a/a to b/a (glob)
moving a/b to b/b (glob)
$ hg ci -m "1 mv a/ b/"
$ hg co -C 0
2 files updated, 0 files merged, 2 files removed, 0 files unresolved
$ echo baz > a/c
$ echo quux > a/d
$ hg add a/c
$ hg ci -m "2 add a/c"
created new head
$ hg merge --debug 1
searching for copies back to rev 1
unmatched files in local:
a/c
unmatched files in other:
b/a
b/b
all copies found (* = to merge, ! = divergent, % = renamed and deleted):
src: 'a/a' -> dst: 'b/a'
src: 'a/b' -> dst: 'b/b'
checking for directory renames
discovered dir src: 'a/' -> dst: 'b/'
pending file src: 'a/c' -> dst: 'b/c'
resolving manifests
branchmerge: True, force: False, partial: False
ancestor: f9b20c0d4c51, local: ce36d17b18fb+, remote: 397f8b00a740
a/a: other deleted -> r
removing a/a
a/b: other deleted -> r
removing a/b
updating: a/b 2/5 files (40.00%)
b/a: remote created -> g
getting b/a
b/b: remote created -> g
getting b/b
updating: b/b 4/5 files (80.00%)
b/c: remote directory rename - move from a/c -> dm
updating: b/c 5/5 files (100.00%)
moving a/c to b/c (glob)
3 files updated, 0 files merged, 2 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ echo a/* b/*
a/d b/a b/b b/c
$ hg st -C
M b/a
M b/b
A b/c
a/c
R a/a
R a/b
R a/c
? a/d
$ hg ci -m "3 merge 2+1"
$ hg debugrename b/c
b/c renamed from a/c:354ae8da6e890359ef49ade27b68bbc361f3ca88 (glob)
$ hg co -C 1
0 files updated, 0 files merged, 1 files removed, 0 files unresolved
$ hg merge --debug 2
searching for copies back to rev 1
unmatched files in local:
b/a
b/b
unmatched files in other:
a/c
all copies found (* = to merge, ! = divergent, % = renamed and deleted):
src: 'a/a' -> dst: 'b/a'
src: 'a/b' -> dst: 'b/b'
checking for directory renames
discovered dir src: 'a/' -> dst: 'b/'
pending file src: 'a/c' -> dst: 'b/c'
resolving manifests
branchmerge: True, force: False, partial: False
ancestor: f9b20c0d4c51, local: 397f8b00a740+, remote: ce36d17b18fb
b/c: local directory rename - get from a/c -> dg
updating: b/c 1/1 files (100.00%)
getting a/c to b/c
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ echo a/* b/*
a/d b/a b/b b/c
$ hg st -C
A b/c
a/c
? a/d
$ hg ci -m "4 merge 1+2"
created new head
$ hg debugrename b/c
b/c renamed from a/c:354ae8da6e890359ef49ade27b68bbc361f3ca88 (glob)
Local directory rename with conflicting file added in remote source directory
and untracked in local target directory.
$ hg co -qC 1
$ echo target > b/c
$ hg merge 2
b/c: untracked file differs
abort: untracked files in working directory differ from files in requested revision
[255]
$ cat b/c
target
but it should succeed if the content matches
$ hg cat -r 2 a/c > b/c
$ hg merge 2
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg st -C
A b/c
a/c
? a/d
Local directory rename with conflicting file added in remote source directory
and committed in local target directory.
$ hg co -qC 1
$ echo target > b/c
$ hg add b/c
$ hg commit -qm 'new file in target directory'
$ hg merge 2
merging b/c and a/c to b/c
warning: conflicts during merge.
merging b/c incomplete! (edit conflicts, then use 'hg resolve --mark')
0 files updated, 0 files merged, 0 files removed, 1 files unresolved
use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon
[1]
$ hg st -A
M b/c
a/c
? a/d
? b/c.orig
C b/a
C b/b
$ cat b/c
<<<<<<< local: f1c50ca4f127 - test: new file in target directory
target
=======
baz
>>>>>>> other: ce36d17b18fb - test: 2 add a/c
$ rm b/c.orig
Remote directory rename with conflicting file added in remote target directory
and committed in local source directory.
$ hg co -qC 2
$ hg st -A
? a/d
C a/a
C a/b
C a/c
$ hg merge 5
merging a/c and b/c to b/c
warning: conflicts during merge.
merging b/c incomplete! (edit conflicts, then use 'hg resolve --mark')
2 files updated, 0 files merged, 2 files removed, 1 files unresolved
use 'hg resolve' to retry unresolved file merges or 'hg update -C .' to abandon
[1]
$ hg st -A
M b/a
M b/b
M b/c
a/c
R a/a
R a/b
R a/c
? a/d
? b/c.orig
$ cat b/c
<<<<<<< local: ce36d17b18fb - test: 2 add a/c
baz
=======
target
>>>>>>> other: f1c50ca4f127 - test: new file in target directory
Second scenario with two repos:
$ cd ..
$ hg init r1
$ cd r1
$ mkdir a
$ echo foo > a/f
$ hg add a
adding a/f (glob)
$ hg ci -m "a/f == foo"
$ cd ..
$ hg clone r1 r2
updating to branch default
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ cd r2
$ hg mv a b
moving a/f to b/f (glob)
$ echo foo1 > b/f
$ hg ci -m" a -> b, b/f == foo1"
$ cd ..
$ cd r1
$ mkdir a/aa
$ echo bar > a/aa/g
$ hg add a/aa
adding a/aa/g (glob)
$ hg ci -m "a/aa/g"
$ hg pull ../r2
pulling from ../r2
searching for changes
adding changesets
adding manifests
adding file changes
added 1 changesets with 1 changes to 1 files (+1 heads)
(run 'hg heads' to see heads, 'hg merge' to merge)
$ hg merge
2 files updated, 0 files merged, 1 files removed, 0 files unresolved
(branch merge, don't forget to commit)
$ hg st -C
M b/f
A b/aa/g
a/aa/g
R a/aa/g
R a/f
$ cd ..