When `nodeType` recovers names and methods, it can overwrite the data if the type is an aliasT. When aliasing a type, do not recover the methods, this will be done in the GTA typeSpec pass.
Related to #1158
It was initially assumed that `nodeType` needed to rebuild the type from scratch, but this is not the case anymore. The existing type constructors are now used in `nodeType` to make it more readable. In doing this some bugs in type strings were found and fixed, along with adding the real package name to the type.
As `ptrOf` is now the only place that pointer types are constructed, it is feasible to cache the pointer type on the value type. To ensures that we have a consistent pointer type for any value type.
As the unsafe and pointer methods in `reflect` are to be depreciated, and seeing no replacement functions, it is now forced that some unsafe is needed to replace this as when and interface is dereferenced it is made unsettable by reflect.
With this in mind, this adds real recursive types by hot swapping the struct field type on the fly. This removes a lot of compensation code, simplifying all previous cases.
**Note:** While the struct field type is swapped for the real type, the type string is not changed. Due to this, unsafe will recreate the same type.
This adds `itype.str` which is a string representation of the type built when the type is built. The goal is to make type comparison simpler and centralise the creation of types just to constructors and `nodeType`. `nodeType` continues to build types in parts so to reuse underlying types better.
Store the interpreter value of the interface object to wrap as
a field called IValue, at offset 0 in wrapper structures.
Update extract to include IValue field.
In typeAssert, detect interface wrapper, and dereference the
interpreter value from IValue wrapper field.
Fixes#1166.
In parsing array type declaration, The type check of array size was
restricted to `int`. Broaden the test to accept any valid integer
kind.
Fixes#1175.
The resolution method was not compliant with the Go specification which
requires to retain the object where the field or method is the most
shallowed.
The detection of ambiguous fields or methods (same depth in different
objects) has also been added.
Fixes#1163.
In selector resolution, struct field matching now precedes
method matching. Before struct field matching could be skipped
in case of a matching method, which is incorrect, as demontrated
by _test/issue-1156.go.
Field lookup has been fixed to operate on recursive structures.
Concrete type values are derived when filling a receiver for
interface methods.
LookupBinField has been fixed to skip non struct values.
LookupMethod has been fixed to iterate on interface values as
well as concrete type values.
Fixes#1156.
In typecheck.go, detect binary methods so we know when to skip the receiver as first parameter when checking function signatures. The signature check is not yet performed, we just avoid a false error.
In cfg.go, take care to label types with isBinMethod field to true whenever a binary method is resolved.
Also, do not attempt to wrap node in functions if the node value is already a binary function.
Fixes#1145.
Fixes#1150
1. When resolving a selector expression involving an aliased type, resolve the aliased type
2. When building an array literal, resolve the aliased type
Aliases of named array and slice types were the only ones that didn't work, but I added the other test cases for the sake of completeness and through testing.
The case of assigning a binary function to a funcT object was
solved elsewhere. Factor the case in genDestValue to apply it
at multiple places.
Fixes#1100.
In binary packages, constants are wrapped in constant.Values, to
support arbitrary precision. Their type must therefore be converted
back to a regular type at import.
Fixes#1101.
Some binary method calls were wrongly rejected. There is still
some ambiguous cases as binary method signature may include or
not the receiver as first argument, depending on how the method
was resolved.
With this fix, `import "golang.org/x/net/html"` doesn't panic
anymore, but not all tests are passing yet, i.e.
`yaegi test golang.org/x/net/html` still has failures, to be
investigated.
Fixes#1107.
The concrete type was not forwarded propertly in case of a binary
expression involving a valueT. The corresponding part in type.go
has been refactored and the now the multi-assign case should be
handled as well.
Fixes#1094.
Interpreted functions were represented in an inconsistent way in the frame: as a node pointer by default, and wrapped in a function wrapper for maps.
We now simply use the default (*node) representation, as elsewhere, so values can be assigned, passed and called as for the other types. The alternative (generating a function wrapper) is more complex, costly and reserved for cases where the interpreted function can be called from the runtime.
Test that a map of functions can store both binary functions from used packages and interpreted ones.
Fixes#1090.
Avoid to test directly for a type category, as it may give wrong
results for aliased types, where the interesting category remains
masked. Instead, use some property helpers, such as isFuncSrc,
isPtrSrc and isInterfaceSrc to check if a type is of source function,
source pointer or source interface respectively (versus runtime
defined function, pointer or interface).
Fixes#1068.
Add missing `sliceT` type category for consistency. Remove
`sizedef` field in `itype` struct. Rename field `size` to `length`.
Clean the various hacks used to cope with the absence of `sliceT`.
This patch brings the following modifications:
- consider that an interface is assignable to another if the former
implements the latter
- call TypeOf() method instead of rtype field when resolving methods, to
handle first met types
- unwrap error interface inplace rather than embedding it in an
interface definition, as lower case named embbeded interface may
not be handled by reflect when lookup for a method.
Fixes#1063. Partially improves #1058.
Functions in a struct fields are always wrapped (as potentially
used by the runtime), so generate a function wrapper also for
closure when assigned to a struct field.
When such a function is called from the interpreter, ensure that
interface arguments are also wrapped so method and receiver resolution
can be performed.
Fixes partially #1043.
The empty interface (interface{}), and its variants (such as []interface{} and map[string]interface{}), are commonly used in Go to (json) Unmarshal arbitrary data. Within Yaegi, all interface types are wrapped in a valueInterface struct in order to retain all the information needed for a consistent internal state (as reflect is not enough to achieve that). However, this wrapping ends up being problematic when it comes to the type assertions related to the aforementioned Unmarshaling.
Therefore, this PR is an attempt to consider the empty interface (and its variants) as an exception within Yaegi, that should never be wrapped within a valueInterface, and to treat it similarly to the other basic Go types. The assumption is that the wrapping should not be needed, as there is no information about implemented methods to maintain.
Fixes#984Fixes#829Fixes#1015
A channel can be used to interchange data with the pre-compiled
runtime and therefore objects impletementing interfaces must be
wrapped if necessary, using genInterfaceWrapper.
A similar treatment could be applied when sending interpreted
functions over a channel, to be provided in a new PR.
Fixes#1010.
Fix the logic to detect recursive struct types, which was giving a false positive.
We now use the local type name as key in tracker map.
A non-regression test case is included (_test/struct49.go).
This completes #1008.
If a struct contains several fields of the same temporary incomplete
type, it could be detected incorrectly as a recursive struct. Pass
a copy of defined types map to avoid this issue.
Fixes#1007.
An undefined type detection function has been added to better diagnose
incomplete type definitions. Implicit type names in interface or struct
declarations are now better handled. The incomplete status is not
fowarded to aliased type declarations to handle circular definitions.
Fixes#999 and #995. Improves #260 (goes farther, but still fails).
In aliased type declarations, when the target type was imported from
an external package rather than declared locally, the aliased type was
overwritten by target, loosing ability to lookup methods on the aliased
type. Aliasing on imported types is now properly detected and handled.
Fixes#971.
The assignable check used to be too strict as it lacked the property that
if an untyped const can be represented as a T, then it is assignable to T.
And we can now use that fixed check to add a missing check: in a return
statement, we now make sure that any of the returned elements are
assignable to what the signature tells us they should be.
There was several issues:
- access to field on pointer to struct from runtime: fix in
lookupBinField
- assign operation was skipped when performed in a comm clause
- the direction of comm clause was wrong if a channel send operation was
performed in a body of a receive comm clause
Fixes#884.
Since the introduction of restricted stdlib and syscall symbols, the
capability of yaegi to interpret itself was broken.
The use of unrestricted symbols is now also controlled by environment
variables, to allow propagation accross nested interpreters.
The interpreter Panic symbol was not wrapped, this is fixed now.
the import path resolution was failing if the working directory was
outside of GOPATH.
The documentation and readme have been ajusted.
Fixes#890.
This change fixes two data races related to composite literal creation.
The first one isn't controversial as it is just about initializing the
variable that contains the values in the right place, i.e. within the
n.exec, so that this variable is local to each potential goroutine,
instead of being racily shared by all goroutines.
The second one is more worrying, i.e. having to protect the node typ
with a mutex, because a call to func (t *itype) refType actually
modifies the itype itself, which means it is not concurrent safe.
The change seems to work, and does not seem to introduce regression, but
it is still a concern as it probably is a sign that more similar
guarding has to be done in several other places.
When searching for a binary method on structures, look up on embedded
fields first, otherwise the resulting index is incorrect, as
reflect.Type.MethodByName succeeds also on container struct.
Fixes#834.
This change fixes two distinct data races:
1) some global vars of type *itype of the interp package are actually
mutated during the lifecycle of an Interpreter. Even worse: if more than
one Interpreter instance are created and used at a given time, they are
actually racing each other for these global vars.
Therefore, this change replaces these global vars with generator
functions that create the needed type on the fly.
2) the symbols given as argument of Interpreter.Use were directly copied
as reference (since they're maps) when mapped inside an Interpreter
instance. Since the usual case is to give the symbols from the stdlib
package, it means when the interpreter mutates its own symbols in
fixStdio, it would actually mutate the corresponding global vars of the
stdlib package. Again, this is at least racy as soon as several
instances of an Intepreter are concurrently running.
This change fixes the race by making sure Interpreter.Use actually
copies the symbol values instead of copying the references.
When determining the size of an array and a symbol is found, the symbol must be a const for the type to be valid.
While it makes sense for this check to be done in type checking, the type can be determined by GTA which would then fail. For now this check is done when getting the node type.
Fixes#825
The trick is that in reflect, the field is called Anonymous, which is
actually a different notion in the Go spec/vocable.
n.b. only works for non-recursive types for now.
Fixes#781
The recent changes that added some redeclaration checks implicitly added more
strictness related to namespaces and scopes which, among other things, broke
some uses that "accidentally" used to work.
For example, given
const script1 = `
import "fmt"
// more code
`
const script2 = `
import "fmt"
// some other code
`
If one Evals script1, then script2, with the same interpreter, without
specifying any scope, as the two fragments would be considered part of the same
(.go file) scope by default, a redeclaration error would be triggered because
import "fmt" is seen twice.
A work-around would have been to specify (a different) i.Name before each Eval
call, so that each script is considered as coming from a different .go file, and
hence are respectively in different scopes with respect to imports.
That lead us to realize we had to make specifying things such as file-scope, and
"incremental mode" (aka REPL), more obvious in the context of an Eval call.
In addition, we want to lay down the foundations for Yaegi being able to behave
more like the go tool wrt to various inputs, i.e. it should be able to take a
package directory, or an import path, as input, instead of just a .go file.
Hence the introduction of a new kind of Eval method (whose signature is not fixed yet):
func (interp *Interpreter) EvalPath(path string) (res reflect.Value, err error)
It partially solves the problem described above because:
1. the path given to EvalPath can be used as the file-scope hint mentioned
above, for now (even though the related implementation details might change).
2. Eval always runs in incremental mode, whereas EvalPath always runs in
non-incremental mode, hence clarifying the situation in that respect.
And to avoid confusion, the Name field of Interpreter is now non-exported,
since it is somewhat redundant with the path argument of EvalPath.
Note that #731 is not fully fixed (and might never be), as a requirement of the
proposed solution is to move the input bits of code into respective files
(instead of leaving them as strings).
Finally, some related bugfixes, documention changes, and some refactoring have
been included. Notably, there is no "empty scope" anymore, i.e. name defaults
to "_.go" when it is not specified.
Updates #731Fixes#778Fixes#798Fixes#789
Co-authored-by: Marc Vertes <mvertes@free.fr>