This patch standardises the load order for modules. Highest priority is trying to load exactly the file the user specified, followed by native extensions, followed by registered extra extensions, etc.
In full, if we require('foo') having registered '.coffee' as an alternative extension, we try and load the following files in order:
foo
foo.js
foo.node
foo.coffee
foo/index.js
foo/index.node
foo/index.coffee
This patch replaces the path.exists check for module loading with a call to
fs.statSync (or fs.stat for require.async) which ensures that it's not trying
to load a directory.
Before there was this comment:
Can't strip trailing slashes since module.js incorrectly
thinks dirname('/a/b/') should yield '/a/b' instead of '/a'.
But now, such thinking is corrected.
This is ever so slightly less efficient than caching based on ID, since the
filename has to be looked up before we can check the cache. However, it's
the most minimal approach possible to get this change in place. Since
require() is a blocking startup-time operation anyway, a bit of slowness is
not a huge problem.
A test involving require.paths modification and absolute loading. Here's the
gist of it.
Files: /p1/foo.js /p2/foo.js
1. Add "/p1" to require.paths.
2. foo1 = require("foo")
3. assert foo1 === require("/p1/foo") (fail)
4. Remove /p1 from require.paths.
5. Add /p2 to require.paths.
6. foo2 = require("foo")
7. assert foo1 !== foo2 (fail)
8. assert foo2 === require("/p2/foo") (fail)
It's an edge case, but it affects how dependencies are mapped by npm.
If your module requires foo-1.2.3, and my module requires foo-2.3.4,
then you should expect to have require("foo") give you foo-1.2.3, and
I should expect require("foo") to give me foo-2.3.4. However, with
module ID based caching, if your code loads *first*, then your "foo"
is THE "foo", so I'll get your version instead of mine.
It hasn't yet been a problem, but only because there are so few
modules, and everyone pretty much uses the latest version all the
time. But as things start to get to the 1.x and 2.x versions, it'll
be an issue, I'm sure. Dependency hell isn't fun, so this is a way to
avoid it before it strikes.
Add NODE_MODULE_CONTEXTS env var
Only one test was modified to check that this works. NEED to go through all
tests and modify them so that
NODE_MODULE_CONTEXTS=1 make test
passes.
Done by not evaluating the code in the first tick.
This breaks one test in test-error-reporting.js but I believe this to be a
V8 error and I have reported it in
http://code.google.com/p/v8/issues/detail?id=764
The fs.readFile bug was hiding another bug that was causing this test
to pass, even so it was broken:
require.async("../fixtures/throws_error1") in test-module-loading.js
This patch fixes the original test by running _compile within a
try..catch block for _loadScript.
_loadScriptSync also had some useless (deprecated?) code for dealing
with module entry point exceptions. This code was also removed for
greater clarity.
- No more single line "node.js:176:9" errors
- No more strange output when error happens on first line due to
module wrapper function.
- A few tests to check these things
Changed ReallyEmit so that it clones the Array of listeners before
processing the emit. Added better tests to make sure that modifying
listeners inside event handlers doesn't cause later listeners to be skipped
or added.
Instead of installing the files in /usr/lib/node/libraries and loading them
from the file system, the files are built-in to the node executable.
However, they are only compiled on demand.
The reasoning is:
1. Allow for more complex internal javascript. In particular,
process.stdout and process.stdin can be js implemented streams.
2. Ease system installs. Loading from disk each time is unnecessary
overhead. Note that there is no "system" path for modules anymore. Only
$HOME/.node_libraries.