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|
package compiler
import (
"fmt"
"io"
"os"
"reflect"
"testing"
)
func printAST(w io.Writer, ast astNode, ruledLine string, childRuledLinePrefix string, withAttrs bool) {
if ast == nil {
return
}
fmt.Fprintf(w, ruledLine)
fmt.Fprintf(w, "node: %v", ast)
if withAttrs {
fmt.Fprintf(w, ", nullable: %v, first: %v, last: %v", ast.nullable(), ast.first(), ast.last())
}
fmt.Fprintf(w, "\n")
left, right := ast.children()
children := []astNode{}
if left != nil {
children = append(children, left)
}
if right != nil {
children = append(children, right)
}
num := len(children)
for i, child := range children {
line := "└─ "
if num > 1 {
if i == 0 {
line = "├─ "
} else if i < num-1 {
line = "│ "
}
}
prefix := "│ "
if i >= num-1 {
prefix = " "
}
printAST(w, child, childRuledLinePrefix+line, childRuledLinePrefix+prefix, withAttrs)
}
}
func TestParser(t *testing.T) {
newCharTok := func(char rune) *token {
return newToken(tokenKindChar, char)
}
rune2Byte := func(char rune, index int) byte {
return []byte(string(char))[index]
}
symPos := func(n uint8) symbolPosition {
return newSymbolPosition(n, false)
}
endPos := func(n uint8) symbolPosition {
return newSymbolPosition(n, true)
}
root, symTab, err := parse(map[int][]byte{
1: []byte("(a|b)*abb"),
})
if err != nil {
t.Fatal(err)
}
if root == nil {
t.Fatal("root of AST is nil")
}
printAST(os.Stdout, root, "", "", false)
{
expectedAST := newConcatNode(
newConcatNode(
newConcatNode(
newConcatNode(
newRepeatNode(
newAltNode(
newSymbolNode(newCharTok('a'), rune2Byte('a', 0), symPos(1)),
newSymbolNode(newCharTok('b'), rune2Byte('b', 0), symPos(2)),
),
),
newSymbolNode(newCharTok('a'), rune2Byte('a', 0), symPos(3)),
),
newSymbolNode(newCharTok('b'), rune2Byte('b', 0), symPos(4)),
),
newSymbolNode(newCharTok('b'), rune2Byte('b', 0), symPos(5)),
),
newEndMarkerNode(1, endPos(6)),
)
testAST(t, expectedAST, root)
}
{
followTab := genFollowTable(root)
if followTab == nil {
t.Fatal("follow table is nil")
}
expectedFollowTab := followTable{
1: newSymbolPositionSet().add(symPos(1)).add(symPos(2)).add(symPos(3)),
2: newSymbolPositionSet().add(symPos(1)).add(symPos(2)).add(symPos(3)),
3: newSymbolPositionSet().add(symPos(4)),
4: newSymbolPositionSet().add(symPos(5)),
5: newSymbolPositionSet().add(endPos(6)),
}
testFollowTable(t, expectedFollowTab, followTab)
}
{
entry := func(v byte) byteRange {
return byteRange{
from: v,
to: v,
}
}
expectedSymTab := &symbolTable{
symPos2Byte: map[symbolPosition]byteRange{
symPos(1): entry(byte('a')),
symPos(2): entry(byte('b')),
symPos(3): entry(byte('a')),
symPos(4): entry(byte('b')),
symPos(5): entry(byte('b')),
},
endPos2ID: map[symbolPosition]int{
endPos(6): 1,
},
}
testSymbolTable(t, expectedSymTab, symTab)
}
}
func testAST(t *testing.T, expected, actual astNode) {
t.Helper()
aTy := reflect.TypeOf(actual)
eTy := reflect.TypeOf(expected)
if eTy != aTy {
t.Fatalf("AST node type is mismatched; want: %v, got: %v", eTy, aTy)
}
if actual == nil {
return
}
switch e := expected.(type) {
case *symbolNode:
a := actual.(*symbolNode)
if a.token.char != e.token.char {
t.Fatalf("character is mismatched; want: '%v' (%v), got: '%v' (%v)", string(e.token.char), e.token.char, string(a.token.char), a.token.char)
}
if a.pos != e.pos {
t.Fatalf("symbol position is mismatched; want: %v, got: %v", e.pos, a.pos)
}
case *endMarkerNode:
a := actual.(*endMarkerNode)
if a.pos != e.pos {
t.Fatalf("symbol position is mismatched; want: %v, got: %v", e.pos, a.pos)
}
}
eLeft, eRight := expected.children()
aLeft, aRight := actual.children()
testAST(t, eLeft, aLeft)
testAST(t, eRight, aRight)
}
func testFollowTable(t *testing.T, expected, actual followTable) {
if len(actual) != len(expected) {
t.Errorf("unexpected number of the follow table entries; want: %v, got: %v", len(expected), len(actual))
}
for ePos, eSet := range expected {
aSet, ok := actual[ePos]
if !ok {
t.Fatalf("follow entry is not found; position: %v, follow: %v", ePos, eSet)
}
if aSet.hash() != eSet.hash() {
t.Fatalf("follow entry of position %v is mismatched; want: %v, got: %v", ePos, aSet, eSet)
}
}
}
func testSymbolTable(t *testing.T, expected, actual *symbolTable) {
t.Helper()
if len(actual.symPos2Byte) != len(expected.symPos2Byte) {
t.Errorf("unexpected symPos2Byte entries; want: %v entries, got: %v entries", len(expected.symPos2Byte), len(actual.symPos2Byte))
}
for ePos, eByte := range expected.symPos2Byte {
byte, ok := actual.symPos2Byte[ePos]
if !ok {
t.Errorf("a symbol position entry was not found: %v -> %v", ePos, eByte)
continue
}
if byte.from != eByte.from || byte.to != eByte.to {
t.Errorf("unexpected symbol position entry; want: %v -> %v, got: %v -> %v", ePos, eByte, ePos, byte)
}
}
if len(actual.endPos2ID) != len(expected.endPos2ID) {
t.Errorf("unexpected endPos2ID entries; want: %v entries, got: %v entries", len(expected.endPos2ID), len(actual.endPos2ID))
}
for ePos, eID := range expected.endPos2ID {
id, ok := actual.endPos2ID[ePos]
if !ok {
t.Errorf("an end position entry was not found: %v -> %v", ePos, eID)
continue
}
if id != eID {
t.Errorf("unexpected end position entry; want: %v -> %v, got: %v -> %v", ePos, eID, ePos, id)
}
}
}
|
