view tests/test-convert-splicemap.t @ 29375:fcaf20175b1b

demandimport: delay loading for "from a import b" with absolute_import

Before this patch, "from a import b" doesn't delay loading module "b",
if absolute_import is enabled, even though "from . import b" does.

For example:

  - it is assumed that extension X has "from P import M" for module M
    under package P with absolute_import feature

  - if importing module M is already delayed before loading extension
    X, loading module M in extension X is delayed until actually
    referring

    util, cmdutil, scmutil or so of Mercurial itself should be
    imported by "from . import M" style before loading extension X

  - otherwise, module M is loaded immediately at loading extension X,
    even if extension X itself isn't used at that "hg" command invocation

    Some minor modules (e.g. filemerge or so) of Mercurial itself
    aren't imported by "from . import M" style before loading
    extension X. And of course, external libraries aren't, too.

This might cause startup performance problem of hg command, because
many bundled extensions already enable absolute_import feature.

To delay loading module for "from a import b" with absolute_import
feature, this patch does below in "from a (or .a) import b" with
absolute_import case:

  1. import root module of "name" by system built-in __import__
     (referred as _origimport)

  2. recurse down the module chain for hierarchical "name"

     This logic can be shared with non absolute_import
     case. Therefore, this patch also centralizes it into chainmodules().

  3. and fall through to process elements in "fromlist" for the leaf
     module of "name"

     Processing elements in "fromlist" is executed in the code path
     after "if _pypy: .... else: ..." clause. Therefore, this patch
     replaces "if _pypy:" with "elif _pypy:" to share it.

At 4f1144c3c72b introducing original "work around" for "from a import
b" case, elements in "fromlist" were imported with "level=level". But
"level" might be grater than 1 (e.g. level=2 in "from .. import b"
case) at demandimport() invocation, and importing direct sub-module in
"fromlist" with level grater than 1 causes unexpected result.

IMHO, this seems main reason of "errors for unknown reason" described
in 4f1144c3c72b, and we don't have to worry about it, because this
issue was already fixed by 78d05778907b.

This is reason why this patch removes "errors for unknown reasons"
comment.

  $ echo "[extensions]" >> $HGRCPATH
  $ echo "convert=" >> $HGRCPATH
  $ glog()
  > {
  >     hg log -G --template '{rev}:{node|short} "{desc|firstline}"\
  >  files: {files}\n' "$@"
  > }
  $ hg init repo1
  $ cd repo1
  $ echo a > a
  $ hg ci -Am adda
  adding a
  $ echo b > b
  $ echo a >> a
  $ hg ci -Am addb
  adding b
  $ PARENTID1=`hg id --debug -i`
  $ echo c > c
  $ hg ci -Am addc
  adding c
  $ PARENTID2=`hg id --debug -i`
  $ cd ..
  $ glog -R repo1
  @  2:e55c719b85b6 "addc" files: c
  |
  o  1:6d4c2037ddc2 "addb" files: a b
  |
  o  0:07f494440405 "adda" files: a
  

  $ hg init repo2
  $ cd repo2
  $ echo b > a
  $ echo d > d
  $ hg ci -Am addaandd
  adding a
  adding d
  $ INVALIDID1=afd12345af
  $ INVALIDID2=28173x36ddd1e67bf7098d541130558ef5534a86
  $ CHILDID1=`hg id --debug -i`
  $ echo d >> d
  $ hg ci -Am changed
  $ CHILDID2=`hg id --debug -i`
  $ echo e > e
  $ hg ci -Am adde
  adding e
  $ cd ..
  $ glog -R repo2
  @  2:a39b65753b0a "adde" files: e
  |
  o  1:e4ea00df9189 "changed" files: d
  |
  o  0:527cdedf31fb "addaandd" files: a d
  

test invalid splicemap1

  $ cat > splicemap <<EOF
  > $CHILDID2
  > EOF
  $ hg convert --splicemap splicemap repo2 repo1
  abort: syntax error in splicemap(1): child parent1[,parent2] expected
  [255]

test invalid splicemap2

  $ cat > splicemap <<EOF
  > $CHILDID2 $PARENTID1, $PARENTID2, $PARENTID2
  > EOF
  $ hg convert --splicemap splicemap repo2 repo1
  abort: syntax error in splicemap(1): child parent1[,parent2] expected
  [255]

test invalid splicemap3

  $ cat > splicemap <<EOF
  > $INVALIDID1 $INVALIDID2
  > EOF
  $ hg convert --splicemap splicemap repo2 repo1
  abort: splicemap entry afd12345af is not a valid revision identifier
  [255]

splice repo2 on repo1

  $ cat > splicemap <<EOF
  > $CHILDID1 $PARENTID1
  > $CHILDID2 $PARENTID2,$CHILDID1
  > 
  > EOF
  $ cat splicemap
  527cdedf31fbd5ea708aa14eeecf53d4676f38db 6d4c2037ddc2cb2627ac3a244ecce35283268f8e
  e4ea00df91897da3079a10fab658c1eddba6617b e55c719b85b60e5102fac26110ba626e7cb6b7dc,527cdedf31fbd5ea708aa14eeecf53d4676f38db
  
  $ hg clone repo1 target1
  updating to branch default
  3 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ hg convert --splicemap splicemap repo2 target1
  scanning source...
  sorting...
  converting...
  2 addaandd
  spliced in 6d4c2037ddc2cb2627ac3a244ecce35283268f8e as parents of 527cdedf31fbd5ea708aa14eeecf53d4676f38db
  1 changed
  spliced in e55c719b85b60e5102fac26110ba626e7cb6b7dc and 527cdedf31fbd5ea708aa14eeecf53d4676f38db as parents of e4ea00df91897da3079a10fab658c1eddba6617b
  0 adde
  $ glog -R target1
  o  5:16bc847b02aa "adde" files: e
  |
  o    4:e30e4fee3418 "changed" files: d
  |\
  | o  3:e673348c3a3c "addaandd" files: a d
  | |
  @ |  2:e55c719b85b6 "addc" files: c
  |/
  o  1:6d4c2037ddc2 "addb" files: a b
  |
  o  0:07f494440405 "adda" files: a
  



Test splicemap and conversion order

  $ hg init ordered
  $ cd ordered
  $ echo a > a
  $ hg ci -Am adda
  adding a
  $ hg branch branch
  marked working directory as branch branch
  (branches are permanent and global, did you want a bookmark?)
  $ echo a >> a
  $ hg ci -Am changea
  $ echo a >> a
  $ hg ci -Am changeaagain
  $ hg up 0
  1 files updated, 0 files merged, 0 files removed, 0 files unresolved
  $ echo b > b
  $ hg ci -Am addb
  adding b

We want 2 to depend on 1 and 3. Since 3 is always converted after 2,
the bug should be exhibited with all conversion orders.

  $ cat > ../splicemap <<EOF
  > `(hg id -r 2 -i --debug)` `(hg id -r 1 -i --debug)`, `(hg id -r 3 -i --debug)`
  > EOF
  $ cd ..
  $ cat splicemap
  7c364e7fa7d70ae525610c016317ed717b519d97 717d54d67e6c31fd75ffef2ff3042bdd98418437, 102a90ea7b4a3361e4082ed620918c261189a36a

Test regular conversion

  $ hg convert --splicemap splicemap ordered ordered-hg1
  initializing destination ordered-hg1 repository
  scanning source...
  sorting...
  converting...
  3 adda
  2 changea
  1 addb
  0 changeaagain
  spliced in 717d54d67e6c31fd75ffef2ff3042bdd98418437 and 102a90ea7b4a3361e4082ed620918c261189a36a as parents of 7c364e7fa7d70ae525610c016317ed717b519d97
  $ glog -R ordered-hg1
  o    3:4cb04b9afbf2 "changeaagain" files: a
  |\
  | o  2:102a90ea7b4a "addb" files: b
  | |
  o |  1:717d54d67e6c "changea" files: a
  |/
  o  0:07f494440405 "adda" files: a
  

Test conversion with parent revisions already in dest, using source
and destination identifiers. Test unknown splicemap target.

  $ hg convert -r1 ordered ordered-hg2
  initializing destination ordered-hg2 repository
  scanning source...
  sorting...
  converting...
  1 adda
  0 changea
  $ hg convert -r3 ordered ordered-hg2
  scanning source...
  sorting...
  converting...
  0 addb
  $ cat > splicemap <<EOF
  > `(hg -R ordered id -r 2 -i --debug)` \
  > `(hg -R ordered-hg2 id -r 1 -i --debug)`,\
  > `(hg -R ordered-hg2 id -r 2 -i --debug)`
  > deadbeef102a90ea7b4a3361e4082ed620918c26 deadbeef102a90ea7b4a3361e4082ed620918c27
  > EOF
  $ hg convert --splicemap splicemap ordered ordered-hg2
  scanning source...
  splice map revision deadbeef102a90ea7b4a3361e4082ed620918c26 is not being converted, ignoring
  sorting...
  converting...
  0 changeaagain
  spliced in 717d54d67e6c31fd75ffef2ff3042bdd98418437 and 102a90ea7b4a3361e4082ed620918c261189a36a as parents of 7c364e7fa7d70ae525610c016317ed717b519d97
  $ glog -R ordered-hg2
  o    3:4cb04b9afbf2 "changeaagain" files: a
  |\
  | o  2:102a90ea7b4a "addb" files: b
  | |
  o |  1:717d54d67e6c "changea" files: a
  |/
  o  0:07f494440405 "adda" files: a
  

Test empty conversion

  $ hg convert --splicemap splicemap ordered ordered-hg2
  scanning source...
  splice map revision deadbeef102a90ea7b4a3361e4082ed620918c26 is not being converted, ignoring
  sorting...
  converting...

Test clonebranches

  $ hg --config convert.hg.clonebranches=true convert \
  >   --splicemap splicemap ordered ordered-hg3
  initializing destination ordered-hg3 repository
  scanning source...
  abort: revision 717d54d67e6c31fd75ffef2ff3042bdd98418437 not found in destination repository (lookups with clonebranches=true are not implemented)
  [255]

Test invalid dependency

  $ cat > splicemap <<EOF
  > `(hg -R ordered id -r 2 -i --debug)` \
  > deadbeef102a90ea7b4a3361e4082ed620918c26,\
  > `(hg -R ordered-hg2 id -r 2 -i --debug)`
  > EOF
  $ hg convert --splicemap splicemap ordered ordered-hg4
  initializing destination ordered-hg4 repository
  scanning source...
  abort: unknown splice map parent: deadbeef102a90ea7b4a3361e4082ed620918c26
  [255]