Fixes multiple issues with stack traces leading to missing
stack trace lines. Also, we no longer put builtin context
on the line which *calls* the builtin as if it was a part
of the builtin itself.
Code for stack trace handling was centralized. We no longer
need traceElement argument in ~every function. Now the stack
trace state is kept solely in the interpreter.
Sort is something that is highly optimized in most languages
and users can expect it to be fast. We can piggyback on
the Go implementation.
This change results in 100x speedup on bench.06.jsonnet.
Currently, `jsonnet.VM#NativeFunction` takes a single argument of type
`jsonnet.nativeFunction`. This is ok for internal use, but because this
type is private to the `jsonnet` package, it is not possible for a
third party to call this function (since it can't instantiate the type).
This commit makes this type public to remedy this problem.
* Location, error formatting and stack trace improvements
* Static context for AST nodes
* Thunks no longer need `name`
* Prototype for showing snippets in error messages (old format still
available)
* Use ast.Function to represent methods and local function sugar.
* Change tests so that the error output is pretty
* Interpreter & runtime - minimal usable version
Accomplishments in this commit:
* Majority of language features implemented:
* Unary operators
* Binary operators
* Conditionals
* Errors
* Indexing arrays
* Indexing objects
* Object inheritance
* Imports
* Functions
* Function calls
* There is a quite nice way for creating builtins
* Static analyzer is there with most of the functionality
* Standard library is included and parts unaffected by missing features
work
* Some bugs in existing parts fixed
* Most positive tests from C++ version pass, the rest is failing mostly
due to missing builtins and comprehensions.
* Some initial structure was created that should allow more incremental
and focused changes in the future PRs.
* Some comments/explanations added
* Panics translated to a little bit more gentle internal errors (with a
link to issues on github).
What still sucks:
* Stack traces & error messages (there's some stuff in place)
* Almost everything is in the same package
* Stuff is exported or unexporeted randomly (see above)
* Missing a few lexing/parsing features
* Missing builtins
* Missing support for extvars and top-level-args
* Checking function arguments is missing
* No clean Go API that commandline and compatibility layer to C can use
* No compatibility layer to C
* Assertions don't work (desugaring level, assertEquals works).
* Manifestation stack traces (and generally it could use some work).
* The way environments are constructed is sometimes suboptimal/clumsy.
