github.com/bir3/gocompiler@v0.3.205/src/xvendor/golang.org/x/tools/internal/facts/imports.go (about)

     1  // Copyright 2018 The Go Authors. All rights reserved.
     2  // Use of this source code is governed by a BSD-style
     3  // license that can be found in the LICENSE file.
     4  
     5  package facts
     6  
     7  import (
     8  	"github.com/bir3/gocompiler/src/go/types"
     9  
    10  	"github.com/bir3/gocompiler/src/xvendor/golang.org/x/tools/internal/typeparams"
    11  )
    12  
    13  // importMap computes the import map for a package by traversing the
    14  // entire exported API each of its imports.
    15  //
    16  // This is a workaround for the fact that we cannot access the map used
    17  // internally by the types.Importer returned by go/importer. The entries
    18  // in this map are the packages and objects that may be relevant to the
    19  // current analysis unit.
    20  //
    21  // Packages in the map that are only indirectly imported may be
    22  // incomplete (!pkg.Complete()).
    23  //
    24  // TODO(adonovan): opt: compute this information more efficiently
    25  // by obtaining it from the internals of the gcexportdata decoder.
    26  func importMap(imports []*types.Package) map[string]*types.Package {
    27  	objects := make(map[types.Object]bool)
    28  	packages := make(map[string]*types.Package)
    29  
    30  	var addObj func(obj types.Object) bool
    31  	var addType func(T types.Type)
    32  
    33  	addObj = func(obj types.Object) bool {
    34  		if !objects[obj] {
    35  			objects[obj] = true
    36  			addType(obj.Type())
    37  			if pkg := obj.Pkg(); pkg != nil {
    38  				packages[pkg.Path()] = pkg
    39  			}
    40  			return true
    41  		}
    42  		return false
    43  	}
    44  
    45  	addType = func(T types.Type) {
    46  		switch T := T.(type) {
    47  		case *types.Basic:
    48  			// nop
    49  		case *types.Named:
    50  			if addObj(T.Obj()) {
    51  				// TODO(taking): Investigate why the Underlying type is not added here.
    52  				for i := 0; i < T.NumMethods(); i++ {
    53  					addObj(T.Method(i))
    54  				}
    55  				if tparams := typeparams.ForNamed(T); tparams != nil {
    56  					for i := 0; i < tparams.Len(); i++ {
    57  						addType(tparams.At(i))
    58  					}
    59  				}
    60  				if targs := typeparams.NamedTypeArgs(T); targs != nil {
    61  					for i := 0; i < targs.Len(); i++ {
    62  						addType(targs.At(i))
    63  					}
    64  				}
    65  			}
    66  		case *types.Pointer:
    67  			addType(T.Elem())
    68  		case *types.Slice:
    69  			addType(T.Elem())
    70  		case *types.Array:
    71  			addType(T.Elem())
    72  		case *types.Chan:
    73  			addType(T.Elem())
    74  		case *types.Map:
    75  			addType(T.Key())
    76  			addType(T.Elem())
    77  		case *types.Signature:
    78  			addType(T.Params())
    79  			addType(T.Results())
    80  			if tparams := typeparams.ForSignature(T); tparams != nil {
    81  				for i := 0; i < tparams.Len(); i++ {
    82  					addType(tparams.At(i))
    83  				}
    84  			}
    85  		case *types.Struct:
    86  			for i := 0; i < T.NumFields(); i++ {
    87  				addObj(T.Field(i))
    88  			}
    89  		case *types.Tuple:
    90  			for i := 0; i < T.Len(); i++ {
    91  				addObj(T.At(i))
    92  			}
    93  		case *types.Interface:
    94  			for i := 0; i < T.NumMethods(); i++ {
    95  				addObj(T.Method(i))
    96  			}
    97  			for i := 0; i < T.NumEmbeddeds(); i++ {
    98  				addType(T.EmbeddedType(i)) // walk Embedded for implicits
    99  			}
   100  		case *typeparams.Union:
   101  			for i := 0; i < T.Len(); i++ {
   102  				addType(T.Term(i).Type())
   103  			}
   104  		case *typeparams.TypeParam:
   105  			if addObj(T.Obj()) {
   106  				addType(T.Constraint())
   107  			}
   108  		}
   109  	}
   110  
   111  	for _, imp := range imports {
   112  		packages[imp.Path()] = imp
   113  
   114  		scope := imp.Scope()
   115  		for _, name := range scope.Names() {
   116  			addObj(scope.Lookup(name))
   117  		}
   118  	}
   119  
   120  	return packages
   121  }