golang.org/x/tools/gopls@v0.15.3/internal/cmd/implementation.go (about)

     1  // Copyright 2019 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 cmd
     6  
     7  import (
     8  	"context"
     9  	"flag"
    10  	"fmt"
    11  	"sort"
    12  
    13  	"golang.org/x/tools/gopls/internal/protocol"
    14  	"golang.org/x/tools/internal/tool"
    15  )
    16  
    17  // implementation implements the implementation verb for gopls
    18  type implementation struct {
    19  	app *Application
    20  }
    21  
    22  func (i *implementation) Name() string      { return "implementation" }
    23  func (i *implementation) Parent() string    { return i.app.Name() }
    24  func (i *implementation) Usage() string     { return "<position>" }
    25  func (i *implementation) ShortHelp() string { return "display selected identifier's implementation" }
    26  func (i *implementation) DetailedHelp(f *flag.FlagSet) {
    27  	fmt.Fprint(f.Output(), `
    28  Example:
    29  
    30  	$ # 1-indexed location (:line:column or :#offset) of the target identifier
    31  	$ gopls implementation helper/helper.go:8:6
    32  	$ gopls implementation helper/helper.go:#53
    33  `)
    34  	printFlagDefaults(f)
    35  }
    36  
    37  func (i *implementation) Run(ctx context.Context, args ...string) error {
    38  	if len(args) != 1 {
    39  		return tool.CommandLineErrorf("implementation expects 1 argument (position)")
    40  	}
    41  
    42  	conn, err := i.app.connect(ctx, nil)
    43  	if err != nil {
    44  		return err
    45  	}
    46  	defer conn.terminate(ctx)
    47  
    48  	from := parseSpan(args[0])
    49  	file, err := conn.openFile(ctx, from.URI())
    50  	if err != nil {
    51  		return err
    52  	}
    53  
    54  	loc, err := file.spanLocation(from)
    55  	if err != nil {
    56  		return err
    57  	}
    58  
    59  	p := protocol.ImplementationParams{
    60  		TextDocumentPositionParams: protocol.LocationTextDocumentPositionParams(loc),
    61  	}
    62  	implementations, err := conn.Implementation(ctx, &p)
    63  	if err != nil {
    64  		return err
    65  	}
    66  
    67  	var spans []string
    68  	for _, impl := range implementations {
    69  		f, err := conn.openFile(ctx, impl.URI)
    70  		if err != nil {
    71  			return err
    72  		}
    73  		span, err := f.locationSpan(impl)
    74  		if err != nil {
    75  			return err
    76  		}
    77  		spans = append(spans, fmt.Sprint(span))
    78  	}
    79  	sort.Strings(spans)
    80  
    81  	for _, s := range spans {
    82  		fmt.Println(s)
    83  	}
    84  
    85  	return nil
    86  }