github.com/amarpal/go-tools@v0.0.0-20240422043104-40142f59f616/simple/s1037/s1037.go (about)

     1  package s1037
     2  
     3  import (
     4  	"go/ast"
     5  
     6  	"github.com/amarpal/go-tools/analysis/code"
     7  	"github.com/amarpal/go-tools/analysis/edit"
     8  	"github.com/amarpal/go-tools/analysis/facts/generated"
     9  	"github.com/amarpal/go-tools/analysis/lint"
    10  	"github.com/amarpal/go-tools/analysis/report"
    11  	"github.com/amarpal/go-tools/pattern"
    12  
    13  	"golang.org/x/tools/go/analysis"
    14  	"golang.org/x/tools/go/analysis/passes/inspect"
    15  )
    16  
    17  var SCAnalyzer = lint.InitializeAnalyzer(&lint.Analyzer{
    18  	Analyzer: &analysis.Analyzer{
    19  		Name:     "S1037",
    20  		Run:      run,
    21  		Requires: []*analysis.Analyzer{inspect.Analyzer, generated.Analyzer},
    22  	},
    23  	Doc: &lint.Documentation{
    24  		Title: `Elaborate way of sleeping`,
    25  		Text: `Using a select statement with a single case receiving
    26  from the result of \'time.After\' is a very elaborate way of sleeping that
    27  can much simpler be expressed with a simple call to time.Sleep.`,
    28  		Since:   "2020.1",
    29  		MergeIf: lint.MergeIfAny,
    30  	},
    31  })
    32  
    33  var Analyzer = SCAnalyzer.Analyzer
    34  
    35  var (
    36  	checkElaborateSleepQ = pattern.MustParse(`(SelectStmt (CommClause (UnaryExpr "<-" (CallExpr (Symbol "time.After") [arg])) body))`)
    37  	checkElaborateSleepR = pattern.MustParse(`(CallExpr (SelectorExpr (Ident "time") (Ident "Sleep")) [arg])`)
    38  )
    39  
    40  func run(pass *analysis.Pass) (interface{}, error) {
    41  	fn := func(node ast.Node) {
    42  		if m, ok := code.Match(pass, checkElaborateSleepQ, node); ok {
    43  			if body, ok := m.State["body"].([]ast.Stmt); ok && len(body) == 0 {
    44  				report.Report(pass, node, "should use time.Sleep instead of elaborate way of sleeping",
    45  					report.ShortRange(),
    46  					report.FilterGenerated(),
    47  					report.Fixes(edit.Fix("Use time.Sleep", edit.ReplaceWithPattern(pass.Fset, node, checkElaborateSleepR, m.State))))
    48  			} else {
    49  				// TODO(dh): we could make a suggested fix if the body
    50  				// doesn't declare or shadow any identifiers
    51  				report.Report(pass, node, "should use time.Sleep instead of elaborate way of sleeping",
    52  					report.ShortRange(),
    53  					report.FilterGenerated())
    54  			}
    55  		}
    56  	}
    57  	code.Preorder(pass, fn, (*ast.SelectStmt)(nil))
    58  	return nil, nil
    59  }