示例#1
0
func extractMultipleStatementsAsFunc(
	astFile *ast.File,
	fileSet *token.FileSet,
	stmtsToExtract []ast.Node,
	parentNode ast.Node,
	extractedFuncName string) {
	params := varIdentsUsedIn(stmtsToExtract)
	varsDeclaredWithinStmtsToExtract := varIdentsDeclaredWithin(stmtsToExtract)
	util.MapStringAstIdentRemoveKeys(params, namesOf(varsDeclaredWithinStmtsToExtract))
	util.MapStringAstIdentRemoveKeys(params, namesOf(globalVarIdents(astFile)))

	allStmts := stmtsFromBlockStmt(parentNode)
	indexOfExtractedStmt := indexOf(stmtsToExtract[0].(ast.Stmt), *allStmts)
	varsUsedAfterwards := overlappingVarsIdentsUsedIn((*allStmts)[indexOfExtractedStmt+len(stmtsToExtract):], varsDeclaredWithinStmtsToExtract)

	newStmt := funcCallStmt(varsUsedAfterwards, extractedFuncName, params, (*allStmts)[indexOfExtractedStmt].Pos())
	replaceStmtsWithFuncCallStmt(newStmt,
		allStmts,
		indexOfExtractedStmt, len(stmtsToExtract))

	areaRemoved := areaRemoved(fileSet, (stmtsToExtract)[0].Pos(), (stmtsToExtract)[len(stmtsToExtract)-1].End())
	lineLengths := lineLengthsFrom(fileSet)
	lineNum, numLinesToCut, newLineLength := replacementModifications(fileSet, (stmtsToExtract)[0].Pos(), (stmtsToExtract)[len(stmtsToExtract)-1].End(), newStmt.End(), lineLengths, areaRemoved)

	shiftPosesAfterPos(astFile, newStmt, (stmtsToExtract)[len(stmtsToExtract)-1].End(), newStmt.End()-stmtsToExtract[len(stmtsToExtract)-1].End())

	multipleStmtFuncDecl := CopyNode(multipleStmtFuncDeclWith(
		extractedFuncName,
		fieldsFrom(params),
		stmtsFromNodes(stmtsToExtract),
		exprsFrom(varsUsedAfterwards),
	)).(*ast.FuncDecl)
	var moveOffset token.Pos
	RecalcPoses(multipleStmtFuncDecl, astFile.End()+2, &moveOffset, 0)
	astFile.Decls = append(astFile.Decls, multipleStmtFuncDecl)

	areaToBeAppended := insertionModificationsForStmts(astFile, multipleStmtFuncDecl, areaRemoved, exprsFrom(varsUsedAfterwards))

	lineLengths = append(
		lineLengths[:lineNum+1],
		lineLengths[lineNum+1+numLinesToCut:]...)
	lineLengths[lineNum] = newLineLength
	lineLengths = append(lineLengths, areaToBeAppended...)

	newFileSet := token.NewFileSet()
	newFileSet.AddFile(fileSet.File(1).Name(), 1, int(astFile.End()))
	newFileSet.File(1).SetLines(ConvertLineLengthsToLineOffsets(lineLengths))
	*fileSet = *newFileSet

	moveComments(astFile, moveOffset /*, needs a range to restict which comments to move*/)

}
示例#2
0
// PathEnclosingInterval returns the node that encloses the source
// interval [start, end), and all its ancestors up to the AST root.
//
// The definition of "enclosing" used by this function considers
// additional whitespace abutting a node to be enclosed by it.
// In this example:
//
//              z := x + y // add them
//                   <-A->
//                  <----B----->
//
// the ast.BinaryExpr(+) node is considered to enclose interval B
// even though its [Pos()..End()) is actually only interval A.
// This behaviour makes user interfaces more tolerant of imperfect
// input.
//
// This function treats tokens as nodes, though they are not included
// in the result. e.g. PathEnclosingInterval("+") returns the
// enclosing ast.BinaryExpr("x + y").
//
// If start==end, the 1-char interval following start is used instead.
//
// The 'exact' result is true if the interval contains only path[0]
// and perhaps some adjacent whitespace.  It is false if the interval
// overlaps multiple children of path[0], or if it contains only
// interior whitespace of path[0].
// In this example:
//
//              z := x + y // add them
//                <--C-->     <---E-->
//                  ^
//                  D
//
// intervals C, D and E are inexact.  C is contained by the
// z-assignment statement, because it spans three of its children (:=,
// x, +).  So too is the 1-char interval D, because it contains only
// interior whitespace of the assignment.  E is considered interior
// whitespace of the BlockStmt containing the assignment.
//
// Precondition: [start, end) both lie within the same file as root.
// TODO(adonovan): return (nil, false) in this case and remove precond.
// Requires FileSet; see tokenFileContainsPos.
//
// Postcondition: path is never nil; it always contains at least 'root'.
//
func PathEnclosingInterval(root *ast.File, start, end token.Pos) (path []ast.Node, exact bool) {
	// fmt.Printf("EnclosingInterval %d %d\n", start, end) // debugging

	// Precondition: node.[Pos..End) and adjoining whitespace contain [start, end).
	var visit func(node ast.Node) bool
	visit = func(node ast.Node) bool {
		path = append(path, node)

		nodePos := node.Pos()
		nodeEnd := node.End()

		// fmt.Printf("visit(%T, %d, %d)\n", node, nodePos, nodeEnd) // debugging

		// Intersect [start, end) with interval of node.
		if start < nodePos {
			start = nodePos
		}
		if end > nodeEnd {
			end = nodeEnd
		}

		// Find sole child that contains [start, end).
		children := childrenOf(node)
		l := len(children)
		for i, child := range children {
			// [childPos, childEnd) is unaugmented interval of child.
			childPos := child.Pos()
			childEnd := child.End()

			// [augPos, augEnd) is whitespace-augmented interval of child.
			augPos := childPos
			augEnd := childEnd
			if i > 0 {
				augPos = children[i-1].End() // start of preceding whitespace
			}
			if i < l-1 {
				nextChildPos := children[i+1].Pos()
				// Does [start, end) lie between child and next child?
				if start >= augEnd && end <= nextChildPos {
					return false // inexact match
				}
				augEnd = nextChildPos // end of following whitespace
			}

			// fmt.Printf("\tchild %d: [%d..%d)\tcontains interval [%d..%d)?\n",
			// 	i, augPos, augEnd, start, end) // debugging

			// Does augmented child strictly contain [start, end)?
			if augPos <= start && end <= augEnd {
				_, isToken := child.(tokenNode)
				return isToken || visit(child)
			}

			// Does [start, end) overlap multiple children?
			// i.e. left-augmented child contains start
			// but LR-augmented child does not contain end.
			if start < childEnd && end > augEnd {
				break
			}
		}

		// No single child contained [start, end),
		// so node is the result.  Is it exact?

		// (It's tempting to put this condition before the
		// child loop, but it gives the wrong result in the
		// case where a node (e.g. ExprStmt) and its sole
		// child have equal intervals.)
		if start == nodePos && end == nodeEnd {
			return true // exact match
		}

		return false // inexact: overlaps multiple children
	}

	if start > end {
		start, end = end, start
	}

	if start < root.End() && end > root.Pos() {
		if start == end {
			end = start + 1 // empty interval => interval of size 1
		}
		exact = visit(root)

		// Reverse the path:
		for i, l := 0, len(path); i < l/2; i++ {
			path[i], path[l-1-i] = path[l-1-i], path[i]
		}
	} else {
		// Selection lies within whitespace preceding the
		// first (or following the last) declaration in the file.
		// The result nonetheless always includes the ast.File.
		path = append(path, root)
	}

	return
}
示例#3
0
func afterImports(file *ast.File) token.Pos {
	return file.End()
}
示例#4
0
func extractExpressionAsFunc(
	astFile *ast.File,
	fileSet *token.FileSet,
	expr ast.Expr,
	parent ast.Node,
	extractedFuncName string) {
	params := varIdentsUsedIn([]ast.Node{expr})
	util.MapStringAstIdentRemoveKeys(params, namesOf(globalVarIdents(astFile)))

	newExpr := CopyNode(callExprWith(extractedFuncName, params)).(ast.Expr)
	RecalcPoses(newExpr, expr.Pos(), nil, 0)
	switch typedNode := parent.(type) {
	case *ast.AssignStmt:
		for i, rhs := range typedNode.Rhs {
			if rhs == expr {
				typedNode.Rhs[i] = newExpr
			}
		}
		for i, lhs := range typedNode.Lhs {
			if lhs == expr {
				typedNode.Lhs[i] = newExpr
			}
		}
	case *ast.CallExpr:
		for i, arg := range typedNode.Args {
			if arg == expr {
				typedNode.Args[i] = newExpr
			}
		}
	case *ast.ExprStmt:
		typedNode.X = newExpr

	case *ast.ReturnStmt:
		for i, result := range typedNode.Results {
			if result == expr {
				typedNode.Results[i] = newExpr
			}
		}
	case *ast.IfStmt:
		if typedNode.Cond == expr {
			typedNode.Cond = newExpr
		}

	case *ast.CaseClause:
		for i, caseExpr := range typedNode.List {
			if caseExpr == expr {
				typedNode.List[i] = newExpr
			}
		}

	case *ast.SwitchStmt:
		if typedNode.Tag == expr {
			typedNode.Tag = newExpr
		}

	case *ast.ForStmt:
		if typedNode.Cond == expr {
			typedNode.Cond = newExpr
		}

	case *ast.RangeStmt:
		if typedNode.Key == expr {
			typedNode.Key = newExpr
		} else if typedNode.Value == expr {
			typedNode.Value = newExpr
		} else if typedNode.X == expr {
			typedNode.X = newExpr
		}

	case *ast.SendStmt:
		if typedNode.Chan == expr {
			typedNode.Chan = newExpr
		} else if typedNode.Value == expr {
			typedNode.Value = newExpr
		}

	case *ast.IncDecStmt:
		if typedNode.X == expr {
			typedNode.X = newExpr
		}

	case *ast.ValueSpec:
		for i, value := range typedNode.Values {
			if value == expr {
				typedNode.Values[i] = newExpr
			}
		}

	default:
		panic(fmt.Sprintf("Type %v not supported yet", reflect.TypeOf(parent)))
	}

	areaRemoved := areaRemoved(fileSet, expr.Pos(), expr.End())
	lineLengths := lineLengthsFrom(fileSet)
	lineNum, numLinesToCut, newLineLength := replacementModifications(fileSet, expr.Pos(), expr.End(), newExpr.End(), lineLengths, areaRemoved)

	shiftPosesAfterPos(astFile, newExpr, expr.End(), newExpr.End()-expr.End())

	singleExprStmtFuncDeclWith := CopyNode(singleExprStmtFuncDeclWith(extractedFuncName, fieldsFrom(params), expr)).(*ast.FuncDecl)
	var moveOffset token.Pos
	RecalcPoses(singleExprStmtFuncDeclWith, astFile.End()+2, &moveOffset, 0)
	astFile.Decls = append(astFile.Decls, singleExprStmtFuncDeclWith)

	areaToBeAppended := insertionModifications(astFile, singleExprStmtFuncDeclWith, areaRemoved)

	lineLengths = append(
		lineLengths[:lineNum+1],
		lineLengths[lineNum+1+numLinesToCut:]...)
	lineLengths[lineNum] = newLineLength
	lineLengths = append(lineLengths, areaToBeAppended...)

	newFileSet := token.NewFileSet()
	newFileSet.AddFile(fileSet.File(1).Name(), 1, int(astFile.End()))
	success := newFileSet.File(1).SetLines(ConvertLineLengthsToLineOffsets(lineLengths))
	if !success {
		panic("Could not SetLines on File.")
	}
	*fileSet = *newFileSet

	moveComments(astFile, moveOffset /*, needs a range to restict which comments to move*/)
}