archive: migrate to the fileprefetch callback mechanism

lfs: migrate to the fileprefetch callback mechanism

cmdutil: convert the prefetchfiles() hook to a callback mechanism (API) Yuya suggested a list of callbacks instead of function wrapping. This means that one extension can't block another from processing the list. .. api:: File prefetching is now handled by registering a callback with scmutil.fileprefetchhooks.

test-narrow: partially stabilize on Windows test-narrow-strip.t is still broken. I don't see any feature condititionals, so it might be an actual problem.

py3: whitelist test-convert-clonebranches.t Differential Revision: https://phab.mercurial-scm.org/D2223

convert: make hg sha1 regex consistently be a bytes Differential Revision: https://phab.mercurial-scm.org/D2222

convcmd: pass encoding name as a sysstr Differential Revision: https://phab.mercurial-scm.org/D2221

convert: open all files in binary mode Differential Revision: https://phab.mercurial-scm.org/D2220

py3: whitelist another 11 passing tests Differential Revision: https://phab.mercurial-scm.org/D2213

util: convert traceback-related sysstrs to sysbytes in getstackframes With this change, test-devel-warnings.t passes except for differences in how ProgrammingError is formatted and one mysterious traceback inside of transaction.__del__. Differential Revision: https://phab.mercurial-scm.org/D2212

util: format line number of stack trace using %d Required on Python 3, functional on Python 2. Differential Revision: https://phab.mercurial-scm.org/D2211

util: call warnings.warn() with a sysstr in nouideprecwarn This preserves nouideprecwarn wanting a bytes, which is consistent with the rest of hg. Differential Revision: https://phab.mercurial-scm.org/D2210

ui: convert stack traces to sysbytes before logging They're coming back as unicodes, so sysbytes seems like the best we can do. This is like D2171 and D2172, but those fail on Python 2.7.5 (seriously!), so this is my version of the same change. I actually wrote this before reviewing those, then discarded it, then came back to it after finding out 2.7.5 is a silly place. Differential Revision: https://phab.mercurial-scm.org/D2209

ui: use pycompat.bytestr() to get a bytes-repr of config default We don't know what type we'll get here, so we need something that'll behave like a repr without returning a unicode. Differential Revision: https://phab.mercurial-scm.org/D2208

tests: add tons of b prefixes in test-devel-warnings.t # skip-blame because it's just b prefixes Differential Revision: https://phab.mercurial-scm.org/D2207

py3: convert traceback representation to bytes when logging Python's APIs should return a system string. We want to use bytes for logging. So convert the traceback to bytes before sending it to the logger. Differential Revision: https://phab.mercurial-scm.org/D2176

py3: convert context to bytes instead of str This yields identical behavior on Python 2 and 3. Differential Revision: https://phab.mercurial-scm.org/D2174

py3: add missing b'' literal to sshprotoext.py Everywhere else in this file uses b''. I must have missed a line when I wrote this code a few days ago. # skip-blame b prefix Differential Revision: https://phab.mercurial-scm.org/D2173

py3: make dummyssh compatible with Python 3 Required encoding a str to bytes and writing bytes to a file descriptor. Differential Revision: https://phab.mercurial-scm.org/D2170

mail: import email.utils not email.Utils email.Utils was renamed to email.utils in Python 2.5. But it appears at some point before Python 2.7 (possibly 2.5) email.Utils was aliased to the new home. So email.utils should be safe for all versions of Python we support. Differential Revision: https://phab.mercurial-scm.org/D2168

py3: cast character set to bytes The returned value from this function is eventually fed into email.charset.Charset.__init__. However, the standard library appears to handle both string types in Python 2 and 3. So there shouldn't be any problem returning a bytes here. Differential Revision: https://phab.mercurial-scm.org/D2167

py3: cast decode() argument to system string The actual types here may be mixed due to string literals and variables from other modules. So a cast is necessary. Differential Revision: https://phab.mercurial-scm.org/D2166

py3: avoid changing dictionary during iteration dict.items() and friends are iterators/views in Python 3. You aren't allowed to mutate the underlying dictionary when iterating on these views. So iterate over a copy of things. Differential Revision: https://phab.mercurial-scm.org/D2164

py3: use raw string for key in **kwargs Otherwise Python 3 is unhappy. We only set a single key here. So I don't think pycompat.strkwargs() is necessary. Differential Revision: https://phab.mercurial-scm.org/D2163

py3: preserve chunks as an iterable of bytes patch.diffstat() returns a bytes. util.chunkbuffer() expects an iterable of bytes. Feeding it a single bytes instance on Python 3 will iterate the characters as integers. This blows up util.chunkbuffer. Differential Revision: https://phab.mercurial-scm.org/D2162

py3: use b'' for changegroup version literals Test extensions aren't currently loaded with our custom module importer. # skip-blame b prefix Differential Revision: https://phab.mercurial-scm.org/D2161

py3: use b'' in inline extension # skip-blame b prefix Differential Revision: https://phab.mercurial-scm.org/D2160

py3: use hex(hasher.digest()) .hexdigest() returns a system str. .digest() consistently returns bytes. Differential Revision: https://phab.mercurial-scm.org/D2159