The existing standalone Query function builds an importer, ssa.Program, oracle,
and query position, executes the query and returns the result.
For clients (such as Frederik Zipp's web-based github.com/fzipp/pythia tool)
that wish to load the program once and make several queries, we now expose
these as separate operations too. Here's a client, in pseudocode:
o := oracle.New(...)
for ... {
qpos := o.ParseQueryPos(...)
res := o.Query(mode, qpos)
print result
}
NB: this is a slight deoptimisation in the one-shot case since we have to
build the entire SSA program with debug info, not just the query package,
since we now don't know the query package at that time.
The 'exact' param to ParseQueryPos needs more thought since its
ideal value is a function of the query mode. This will do for now.
Details:
- expose Oracle type, New() func and Query() method.
- expose QueryPos type and ParseQueryPos func.
- improved package doc comment.
- un-exposed the "needs" bits.
- added test.
R=crawshaw
CC=frederik.zipp, golang-dev
https://golang.org/cl/13810043
Full help is only displayed when -help is requested;
CLI usage errors just remind the the user of this flag.
R=r, crawshaw
CC=golang-dev
https://golang.org/cl/13523048
Every one of the oracle's query modes needs to have typed ASTs
available, at least transiently, so that the -pos flag can be
interpreted. (The only mode that doesn't need the -pos flag
is callgraph, but that needs PTA.) So we hard-code it to true.
This change fixes a bug in the 'implements' query that causes
-pos parsing to fail. (This wasn't exposed by the tests
because they are degenerate in that the query always occurs in
the main package, which is specified ad-hoc, i.e. as a source
file not an import path. That's unfortunate, but this
change renders the distinction uninteresting in future.)
R=crawshaw, dominik.honnef
CC=golang-dev
https://golang.org/cl/13334050
+ test.
Also:
- provide non-nil map to Importer.doImport0() to avoid a crash.
- reorganize oracle "needs" bits.
- reduce "needs" of 'freevars' and 'implements' queries by avoiding
ssa.Packages when types.Package suffices.
R=crawshaw
CC=golang-dev
https://golang.org/cl/13421046
Motivation: pointer analysis tools (like the oracle) want the
user to specify a set of initial packages, like 'go test'.
This change enables the user to specify a set of packages on
the command line using importer.LoadInitialPackages(args).
Each argument is interpreted as either:
- a comma-separated list of *.go source files together
comprising one non-importable ad-hoc package.
e.g. "src/pkg/net/http/triv.go" gives us [main].
- an import path, denoting both the imported package
and its non-importable external test package, if any.
e.g. "fmt" gives us [fmt, fmt_test].
Current type-checker limitations mean that only the first
import path may contribute tests: multiple packages augmented
by *_test.go files could create import cycles, which 'go test'
avoids by building a separate executable for each one.
That approach is less attractive for static analysis.
Details: (many files touched, but importer.go is the crux)
importer:
- PackageInfo.Importable boolean indicates whether
package is importable.
- un-expose Importer.Packages; expose AllPackages() instead.
- CreatePackageFromArgs has become LoadInitialPackages.
- imports() moved to util.go, renamed importsOf().
- InitialPackagesUsage usage message exported to clients.
- the package name for ad-hoc packages now comes from the
'package' decl, not "main".
ssa.Program:
- added CreatePackages() method
- PackagesByPath un-exposed, renamed 'imported'.
- expose AllPackages and ImportedPackage accessors.
oracle:
- describe: explain and workaround a go/types bug.
Misc:
- Removed various unnecessary error.Error() calls in Printf args.
R=crawshaw
CC=golang-dev
https://golang.org/cl/13579043
The previous notation (sans '#') now yields an error but is
"reserved for future use", e.g. to denote line/column offsets.
Will implement as needed.
R=r, crawshaw
CC=golang-dev
https://golang.org/cl/13526043
1. ParseFiles (in util.go) parses each file in its own goroutine.
2. (*Importer).LoadPackage asynchronously prefetches the
import graph by scanning the imports of each loaded package
and calling LoadPackage on each one.
LoadPackage is now thread-safe and idempotent: it uses a
condition variable per package; the first goroutine to
request a package becomes responsible for loading it and
broadcasts to the others (waiting) when it becomes ready.
ssadump runs 34% faster when loading the oracle.
Also, refactorings:
- delete SourceLoader mechanism; just expose go/build.Context directly.
- CreateSourcePackage now also returns an error directly,
rather than via PackageInfo.Err, since every client wants that.
R=crawshaw
CC=golang-dev
https://golang.org/cl/13509045
See json.go for interface specification.
Example usage:
% oracle -format=json -mode=callgraph code.google.com/p/go.tools/cmd/oracle
+ Tests, based on (small) golden files.
Overview:
Each <query>Result structure has been "lowered" so that all
but the most trivial logic in each display() function has
been moved to the main query.
Each one now has a toJSON method that populates a json.Result
struct. Though the <query>Result structs are similar to the
correponding JSON protocol, they're not close enough to be
used directly; for example, the former contain richer
semantic entities (token.Pos, ast.Expr, ssa.Value,
pointer.Pointer, etc) whereas JSON contains only their
printed forms using Go basic types.
The choices of what levels of abstractions the two sets of
structs should have is somewhat arbitrary. We may want
richer information in the JSON output in future.
Details:
- oracle.Main has been split into oracle.Query() and the
printing of the oracle.Result.
- the display() method no longer needs an *oracle param, only
a print function.
- callees: sort the result for determinism.
- callees: compute the union across all contexts.
- callers: sort the results for determinism.
- describe(package): fixed a bug in the predicate for method
accessibility: an unexported method defined in pkg A may
belong to a type defined in package B (via
embedding/promotion) and may thus be accessible to A. New
accessibleMethods() utility fixes this.
- describe(type): filter methods by accessibility.
- added tests of 'callgraph'.
- pointer: eliminated the 'caller CallGraphNode' parameter from
pointer.Context.Call callback since it was redundant w.r.t
site.Caller().
- added warning if CGO_ENABLED is unset.
R=crawshaw
CC=golang-dev
https://golang.org/cl/13270045
Pro: no shell quotation needed.
Con: can't be parsed by (the perpetually useless) Scanf.
R=crawshaw, dgryski
CC=golang-dev
https://golang.org/cl/13441043
+ Tests.
+ Emacs integration.
+ Emacs integration test.
+ very rudimentary Vim integration. Needs some love from a Vim user.
TODO (in follow-ups):
- More tests would be good.
We'll need to make the output order deterministic in more places.
- Documentation.
R=gri, crawshaw, dominik.honnef
CC=golang-dev
https://golang.org/cl/9502043
