X-Git-Url: https://git.josue.xyz/?a=blobdiff_plain;f=.config%2Fcoc%2Fextensions%2Fcoc-go-data%2Ftools%2Fpkg%2Fmod%2Fgolang.org%2Fx%2Ftools%40v0.1.1-0.20210319172145-bda8f5cee399%2Fgo%2Fpackages%2Fdoc.go;fp=.config%2Fcoc%2Fextensions%2Fcoc-go-data%2Ftools%2Fpkg%2Fmod%2Fgolang.org%2Fx%2Ftools%40v0.1.1-0.20210319172145-bda8f5cee399%2Fgo%2Fpackages%2Fdoc.go;h=4bfe28a51ff520c88d0b1f37724d9e1e85b9b603;hb=3c06164f15bd10aed7d66b6314764a2961a14762;hp=0000000000000000000000000000000000000000;hpb=0e9c3ceb40901f4d44981c1376cb9e23a248e006;p=dotfiles%2F.git diff --git a/.config/coc/extensions/coc-go-data/tools/pkg/mod/golang.org/x/tools@v0.1.1-0.20210319172145-bda8f5cee399/go/packages/doc.go b/.config/coc/extensions/coc-go-data/tools/pkg/mod/golang.org/x/tools@v0.1.1-0.20210319172145-bda8f5cee399/go/packages/doc.go new file mode 100644 index 00000000..4bfe28a5 --- /dev/null +++ b/.config/coc/extensions/coc-go-data/tools/pkg/mod/golang.org/x/tools@v0.1.1-0.20210319172145-bda8f5cee399/go/packages/doc.go @@ -0,0 +1,221 @@ +// Copyright 2018 The Go Authors. All rights reserved. +// Use of this source code is governed by a BSD-style +// license that can be found in the LICENSE file. + +/* +Package packages loads Go packages for inspection and analysis. + +The Load function takes as input a list of patterns and return a list of Package +structs describing individual packages matched by those patterns. +The LoadMode controls the amount of detail in the loaded packages. + +Load passes most patterns directly to the underlying build tool, +but all patterns with the prefix "query=", where query is a +non-empty string of letters from [a-z], are reserved and may be +interpreted as query operators. + +Two query operators are currently supported: "file" and "pattern". + +The query "file=path/to/file.go" matches the package or packages enclosing +the Go source file path/to/file.go. For example "file=~/go/src/fmt/print.go" +might return the packages "fmt" and "fmt [fmt.test]". + +The query "pattern=string" causes "string" to be passed directly to +the underlying build tool. In most cases this is unnecessary, +but an application can use Load("pattern=" + x) as an escaping mechanism +to ensure that x is not interpreted as a query operator if it contains '='. + +All other query operators are reserved for future use and currently +cause Load to report an error. + +The Package struct provides basic information about the package, including + + - ID, a unique identifier for the package in the returned set; + - GoFiles, the names of the package's Go source files; + - Imports, a map from source import strings to the Packages they name; + - Types, the type information for the package's exported symbols; + - Syntax, the parsed syntax trees for the package's source code; and + - TypeInfo, the result of a complete type-check of the package syntax trees. + +(See the documentation for type Package for the complete list of fields +and more detailed descriptions.) + +For example, + + Load(nil, "bytes", "unicode...") + +returns four Package structs describing the standard library packages +bytes, unicode, unicode/utf16, and unicode/utf8. Note that one pattern +can match multiple packages and that a package might be matched by +multiple patterns: in general it is not possible to determine which +packages correspond to which patterns. + +Note that the list returned by Load contains only the packages matched +by the patterns. Their dependencies can be found by walking the import +graph using the Imports fields. + +The Load function can be configured by passing a pointer to a Config as +the first argument. A nil Config is equivalent to the zero Config, which +causes Load to run in LoadFiles mode, collecting minimal information. +See the documentation for type Config for details. + +As noted earlier, the Config.Mode controls the amount of detail +reported about the loaded packages. See the documentation for type LoadMode +for details. + +Most tools should pass their command-line arguments (after any flags) +uninterpreted to the loader, so that the loader can interpret them +according to the conventions of the underlying build system. +See the Example function for typical usage. + +*/ +package packages // import "golang.org/x/tools/go/packages" + +/* + +Motivation and design considerations + +The new package's design solves problems addressed by two existing +packages: go/build, which locates and describes packages, and +golang.org/x/tools/go/loader, which loads, parses and type-checks them. +The go/build.Package structure encodes too much of the 'go build' way +of organizing projects, leaving us in need of a data type that describes a +package of Go source code independent of the underlying build system. +We wanted something that works equally well with go build and vgo, and +also other build systems such as Bazel and Blaze, making it possible to +construct analysis tools that work in all these environments. +Tools such as errcheck and staticcheck were essentially unavailable to +the Go community at Google, and some of Google's internal tools for Go +are unavailable externally. +This new package provides a uniform way to obtain package metadata by +querying each of these build systems, optionally supporting their +preferred command-line notations for packages, so that tools integrate +neatly with users' build environments. The Metadata query function +executes an external query tool appropriate to the current workspace. + +Loading packages always returns the complete import graph "all the way down", +even if all you want is information about a single package, because the query +mechanisms of all the build systems we currently support ({go,vgo} list, and +blaze/bazel aspect-based query) cannot provide detailed information +about one package without visiting all its dependencies too, so there is +no additional asymptotic cost to providing transitive information. +(This property might not be true of a hypothetical 5th build system.) + +In calls to TypeCheck, all initial packages, and any package that +transitively depends on one of them, must be loaded from source. +Consider A->B->C->D->E: if A,C are initial, A,B,C must be loaded from +source; D may be loaded from export data, and E may not be loaded at all +(though it's possible that D's export data mentions it, so a +types.Package may be created for it and exposed.) + +The old loader had a feature to suppress type-checking of function +bodies on a per-package basis, primarily intended to reduce the work of +obtaining type information for imported packages. Now that imports are +satisfied by export data, the optimization no longer seems necessary. + +Despite some early attempts, the old loader did not exploit export data, +instead always using the equivalent of WholeProgram mode. This was due +to the complexity of mixing source and export data packages (now +resolved by the upward traversal mentioned above), and because export data +files were nearly always missing or stale. Now that 'go build' supports +caching, all the underlying build systems can guarantee to produce +export data in a reasonable (amortized) time. + +Test "main" packages synthesized by the build system are now reported as +first-class packages, avoiding the need for clients (such as go/ssa) to +reinvent this generation logic. + +One way in which go/packages is simpler than the old loader is in its +treatment of in-package tests. In-package tests are packages that +consist of all the files of the library under test, plus the test files. +The old loader constructed in-package tests by a two-phase process of +mutation called "augmentation": first it would construct and type check +all the ordinary library packages and type-check the packages that +depend on them; then it would add more (test) files to the package and +type-check again. This two-phase approach had four major problems: +1) in processing the tests, the loader modified the library package, + leaving no way for a client application to see both the test + package and the library package; one would mutate into the other. +2) because test files can declare additional methods on types defined in + the library portion of the package, the dispatch of method calls in + the library portion was affected by the presence of the test files. + This should have been a clue that the packages were logically + different. +3) this model of "augmentation" assumed at most one in-package test + per library package, which is true of projects using 'go build', + but not other build systems. +4) because of the two-phase nature of test processing, all packages that + import the library package had to be processed before augmentation, + forcing a "one-shot" API and preventing the client from calling Load + in several times in sequence as is now possible in WholeProgram mode. + (TypeCheck mode has a similar one-shot restriction for a different reason.) + +Early drafts of this package supported "multi-shot" operation. +Although it allowed clients to make a sequence of calls (or concurrent +calls) to Load, building up the graph of Packages incrementally, +it was of marginal value: it complicated the API +(since it allowed some options to vary across calls but not others), +it complicated the implementation, +it cannot be made to work in Types mode, as explained above, +and it was less efficient than making one combined call (when this is possible). +Among the clients we have inspected, none made multiple calls to load +but could not be easily and satisfactorily modified to make only a single call. +However, applications changes may be required. +For example, the ssadump command loads the user-specified packages +and in addition the runtime package. It is tempting to simply append +"runtime" to the user-provided list, but that does not work if the user +specified an ad-hoc package such as [a.go b.go]. +Instead, ssadump no longer requests the runtime package, +but seeks it among the dependencies of the user-specified packages, +and emits an error if it is not found. + +Overlays: The Overlay field in the Config allows providing alternate contents +for Go source files, by providing a mapping from file path to contents. +go/packages will pull in new imports added in overlay files when go/packages +is run in LoadImports mode or greater. +Overlay support for the go list driver isn't complete yet: if the file doesn't +exist on disk, it will only be recognized in an overlay if it is a non-test file +and the package would be reported even without the overlay. + +Questions & Tasks + +- Add GOARCH/GOOS? + They are not portable concepts, but could be made portable. + Our goal has been to allow users to express themselves using the conventions + of the underlying build system: if the build system honors GOARCH + during a build and during a metadata query, then so should + applications built atop that query mechanism. + Conversely, if the target architecture of the build is determined by + command-line flags, the application can pass the relevant + flags through to the build system using a command such as: + myapp -query_flag="--cpu=amd64" -query_flag="--os=darwin" + However, this approach is low-level, unwieldy, and non-portable. + GOOS and GOARCH seem important enough to warrant a dedicated option. + +- How should we handle partial failures such as a mixture of good and + malformed patterns, existing and non-existent packages, successful and + failed builds, import failures, import cycles, and so on, in a call to + Load? + +- Support bazel, blaze, and go1.10 list, not just go1.11 list. + +- Handle (and test) various partial success cases, e.g. + a mixture of good packages and: + invalid patterns + nonexistent packages + empty packages + packages with malformed package or import declarations + unreadable files + import cycles + other parse errors + type errors + Make sure we record errors at the correct place in the graph. + +- Missing packages among initial arguments are not reported. + Return bogus packages for them, like golist does. + +- "undeclared name" errors (for example) are reported out of source file + order. I suspect this is due to the breadth-first resolution now used + by go/types. Is that a bug? Discuss with gri. + +*/