func()

in tool/instrument/trampoline.go [406:483]

• 72 lines of code
• 18 McCabe index (conditional complexity)

func (rp *RuleProcessor) replenishCallContext(onEnter bool) bool {
	funcDecl := rp.onEnterHookFunc
	if !onEnter {
		funcDecl = rp.onExitHookFunc
	}
	for _, stmt := range funcDecl.Body.List {
		if assignStmt, ok := stmt.(*dst.AssignStmt); ok {
			lhs := assignStmt.Lhs
			if sel, ok := lhs[0].(*dst.SelectorExpr); ok {
				switch sel.Sel.Name {
				case TrampolineFuncNameIdentifier:
					util.Assert(onEnter, "sanity check")
					// callContext.FuncName = "..."
					rhs := assignStmt.Rhs
					if len(rhs) == 1 {
						rhsExpr := rhs[0]
						if basicLit, ok := rhsExpr.(*dst.BasicLit); ok {
							if basicLit.Kind == token.STRING {
								rawFuncName := rp.rawFunc.Name.Name
								basicLit.Value = strconv.Quote(rawFuncName)
							} else {
								return false // ill-formed AST
							}
						} else {
							return false // ill-formed AST
						}
					} else {
						return false // ill-formed AST
					}
				case TrampolinePackageNameIdentifier:
					util.Assert(onEnter, "sanity check")
					// callContext.PackageName = "..."
					rhs := assignStmt.Rhs
					if len(rhs) == 1 {
						rhsExpr := rhs[0]
						if basicLit, ok := rhsExpr.(*dst.BasicLit); ok {
							if basicLit.Kind == token.STRING {
								pkgName := rp.target.Name.Name
								basicLit.Value = strconv.Quote(pkgName)
							} else {
								return false // ill-formed AST
							}
						} else {
							return false // ill-formed AST
						}
					} else {
						return false // ill-formed AST
					}
				default:
					// callContext.Params = []interface{}{...} or
					// callContext.(*CallContextImpl).Params[0] = &int
					rhs := assignStmt.Rhs
					if len(rhs) == 1 {
						rhsExpr := rhs[0]
						if compositeLit, ok := rhsExpr.(*dst.CompositeLit); ok {
							elems := compositeLit.Elts
							names := getNames(funcDecl.Type.Params)
							for i, name := range names {
								if i == 0 && !onEnter {
									// SKip first callContext parameter for onExit
									continue
								}
								elems = append(elems, util.Ident(name))
							}
							compositeLit.Elts = elems
						} else {
							return false // ill-formed AST
						}
					} else {
						return false // ill-formed AST
					}
				}
			}

		}
	}
	return true
}