archive: drop the leading '.' path component from the prefix (issue4634)

Unix utilities like tar will happily prefix the files it packs with './', but
annoyingly, Windows Explorer will not show these packed files when it opens the
archive.  Since there doesn't seem to be a point in including './' in the path
names, just drop it.  The default 'hg archive' prefix is the basename of the
archive, so specifying '.' allows for that default to be disabled completely.

mercurial/archival.py

@@ -37,6 +37,10 b' def tidyprefix(dest, kind, prefix):'
     prefix = util.pconvert(lpfx)
     if not prefix.endswith('/'):
         prefix += '/'
+    # Drop the leading '.' path component if present, so Windows can read the
+    # zip files (issue4634)
+    if prefix.startswith('./'):
+        prefix = prefix[2:]
     if prefix.startswith('../') or os.path.isabs(lpfx) or '/../' in prefix:
         raise util.Abort(_('archive prefix contains illegal components'))
     return prefix

tests/test-subrepo-deep-nested-change.t

@@ -309,17 +309,17 b' Exclude large files from main and sub-su'
 
 Exclude normal files from main and sub-sub repo
 
-  $ hg --config extensions.largefiles= archive -S -X '**.txt' ../archive_lf.tgz
+  $ hg --config extensions.largefiles= archive -S -X '**.txt' -p '.' ../archive_lf.tgz
   $ tar -tzf ../archive_lf.tgz | sort
-  archive_lf/.hgsub
-  archive_lf/.hgsubstate
-  archive_lf/large.bin
-  archive_lf/main
-  archive_lf/sub1/.hgsub
-  archive_lf/sub1/.hgsubstate
-  archive_lf/sub1/sub1
-  archive_lf/sub1/sub2/large.bin
-  archive_lf/sub1/sub2/sub2
+  .hgsub
+  .hgsubstate
+  large.bin
+  main
+  sub1/.hgsub
+  sub1/.hgsubstate
+  sub1/sub1
+  sub1/sub2/large.bin
+  sub1/sub2/sub2
 
 Include normal files from within a largefiles subrepo
 

tests/test-subrepo-git.t

@@ -325,13 +325,13 b' archive subrepos'
   ../archive_x/s
   ../archive_x/s/g
 
-  $ hg -R ../tc archive -S ../archive.tgz 2>/dev/null
+  $ hg -R ../tc archive -S ../archive.tgz --prefix '.' 2>/dev/null
   $ tar -tzf ../archive.tgz | sort
-  archive/.hg_archival.txt
-  archive/.hgsub
-  archive/.hgsubstate
-  archive/a
-  archive/s/g
+  .hg_archival.txt
+  .hgsub
+  .hgsubstate
+  a
+  s/g
 
 create nested repo
 

tests/test-subrepo-recursion.t

@@ -312,7 +312,7 b' only show up in the test output, not in '
 
 Test archiving to zip file (unzip output is unstable):
 
-  $ hg archive --subrepos ../archive.zip
+  $ hg archive --subrepos --prefix '.' ../archive.zip
   \r (no-eol) (esc)
   archiving [                                           ] 0/3\r (no-eol) (esc)
   archiving [                                           ] 0/3\r (no-eol) (esc)
@@ -339,6 +339,20 b' Test archiving to zip file (unzip output'
   archiving (foo/bar) [================================>] 1/1\r (no-eol) (glob) (esc)
   archiving (foo/bar) [================================>] 1/1\r (no-eol) (glob) (esc)
                                                               \r (no-eol) (esc)
+  $ unzip -l ../archive.zip
+  Archive:  ../archive.zip
+    Length      Date    Time    Name
+  ---------  ---------- -----   ----
+        172  01-01-1980 00:00   .hg_archival.txt
+         10  01-01-1980 00:00   .hgsub
+         45  01-01-1980 00:00   .hgsubstate
+          3  01-01-1980 00:00   x.txt
+         10  01-01-1980 00:00   foo/.hgsub
+         45  01-01-1980 00:00   foo/.hgsubstate
+          9  01-01-1980 00:00   foo/y.txt
+          9  01-01-1980 00:00   foo/bar/z.txt
+  ---------                     -------
+        303                     8 files
 
 Test archiving a revision that references a subrepo that is not yet
 cloned:
@@ -363,7 +377,7 b' cloned:'
 
   $ cd ../empty
 #if hardlink
-  $ hg archive --subrepos -r tip ../archive.tar.gz
+  $ hg archive --subrepos -r tip --prefix './' ../archive.tar.gz
   \r (no-eol) (esc)
   archiving [                                           ] 0/3\r (no-eol) (esc)
   archiving [                                           ] 0/3\r (no-eol) (esc)
@@ -413,7 +427,7 b' cloned:'
 #else
 Note there's a slight output glitch on non-hardlink systems: the last
 "linking" progress topic never gets closed, leading to slight output corruption on that platform.
-  $ hg archive --subrepos -r tip ../archive.tar.gz
+  $ hg archive --subrepos -r tip --prefix './' ../archive.tar.gz
   \r (no-eol) (esc)
   archiving [                                           ] 0/3\r (no-eol) (esc)
   archiving [                                           ] 0/3\r (no-eol) (esc)
@@ -437,14 +451,14 b" Note there's a slight output glitch on n"
 Archive + subrepos uses '/' for all component separators
 
   $ tar -tzf ../archive.tar.gz | sort
-  archive/.hg_archival.txt
-  archive/.hgsub
-  archive/.hgsubstate
-  archive/foo/.hgsub
-  archive/foo/.hgsubstate
-  archive/foo/bar/z.txt
-  archive/foo/y.txt
-  archive/x.txt
+  .hg_archival.txt
+  .hgsub
+  .hgsubstate
+  foo/.hgsub
+  foo/.hgsubstate
+  foo/bar/z.txt
+  foo/y.txt
+  x.txt
 
 The newly cloned subrepos contain no working copy: