Add start of jsonpath parser

1 files changed, 172 insertions, 0 deletions

diff --git a/jsonpath/lexer_test.go b/jsonpath/lexer_test.go
new file mode 100644
index 0000000..504d413
--- /dev/null
+++ b/jsonpath/lexer_test.go
@@ -0,0 +1,172 @@
+package jsonpath
+
+import (
+	"testing"
+
+	"src.userspace.com.au/query/lexer"
+)
+
+func TestValidStates(t *testing.T) {
+	tests := []struct {
+		path   string
+		tokens []lexer.Token
+	}{
+		{
+			path: "$.test",
+			tokens: []lexer.Token{
+				lexer.Token{Type: TAbsolute, Value: "$"},
+				lexer.Token{Type: TChildDot, Value: "."},
+				lexer.Token{Type: TName, Value: "test"},
+			},
+		},
+		{
+			path: "$[test]",
+			tokens: []lexer.Token{
+				lexer.Token{Type: TAbsolute, Value: "$"},
+				lexer.Token{Type: TChildStart, Value: "["},
+				lexer.Token{Type: TName, Value: "test"},
+				lexer.Token{Type: TChildEnd, Value: "]"},
+			},
+		},
+		{
+			path: "$[one][two]",
+			tokens: []lexer.Token{
+				lexer.Token{Type: TAbsolute, Value: "$"},
+				lexer.Token{Type: TChildStart, Value: "["},
+				lexer.Token{Type: TName, Value: "one"},
+				lexer.Token{Type: TChildEnd, Value: "]"},
+				lexer.Token{Type: TChildStart, Value: "["},
+				lexer.Token{Type: TName, Value: "two"},
+				lexer.Token{Type: TChildEnd, Value: "]"},
+			},
+		},
+		{
+			path: "$.one.two",
+			tokens: []lexer.Token{
+				lexer.Token{Type: TAbsolute, Value: "$"},
+				lexer.Token{Type: TChildDot, Value: "."},
+				lexer.Token{Type: TName, Value: "one"},
+				lexer.Token{Type: TChildEnd, Value: ""},
+				lexer.Token{Type: TChildDot, Value: "."},
+				lexer.Token{Type: TName, Value: "two"},
+			},
+		},
+		{
+			path: "$[*]",
+			tokens: []lexer.Token{
+				lexer.Token{Type: TAbsolute, Value: "$"},
+				lexer.Token{Type: TChildStart, Value: "["},
+				lexer.Token{Type: TWildcard, Value: "*"},
+				lexer.Token{Type: TChildEnd, Value: "]"},
+			},
+		},
+		{
+			path: "$[one][*]",
+			tokens: []lexer.Token{
+				lexer.Token{Type: TAbsolute, Value: "$"},
+				lexer.Token{Type: TChildStart, Value: "["},
+				lexer.Token{Type: TName, Value: "one"},
+				lexer.Token{Type: TChildEnd, Value: "]"},
+				lexer.Token{Type: TChildStart, Value: "["},
+				lexer.Token{Type: TWildcard, Value: "*"},
+				lexer.Token{Type: TChildEnd, Value: "]"},
+			},
+		},
+		{
+			path: "$.one[1,2,3]",
+			tokens: []lexer.Token{
+				lexer.Token{Type: TAbsolute, Value: "$"},
+				lexer.Token{Type: TChildDot, Value: "."},
+				lexer.Token{Type: TName, Value: "one"},
+				lexer.Token{Type: TPredicateStart, Value: "["},
+				lexer.Token{Type: TNumber, Value: "1"},
+				lexer.Token{Type: TUnion, Value: ","},
+				lexer.Token{Type: TNumber, Value: "2"},
+				lexer.Token{Type: TUnion, Value: ","},
+				lexer.Token{Type: TNumber, Value: "3"},
+				lexer.Token{Type: TPredicateEnd, Value: "]"},
+			},
+		},
+		{
+			path: "$.one[1:3]",
+			tokens: []lexer.Token{
+				lexer.Token{Type: TAbsolute, Value: "$"},
+				lexer.Token{Type: TChildDot, Value: "."},
+				lexer.Token{Type: TName, Value: "one"},
+				lexer.Token{Type: TPredicateStart, Value: "["},
+				lexer.Token{Type: TNumber, Value: "1"},
+				lexer.Token{Type: TRange, Value: ":"},
+				lexer.Token{Type: TNumber, Value: "3"},
+				lexer.Token{Type: TPredicateEnd, Value: "]"},
+			},
+		},
+		{
+			path: "$.one[:3]",
+			tokens: []lexer.Token{
+				lexer.Token{Type: TAbsolute, Value: "$"},
+				lexer.Token{Type: TChildDot, Value: "."},
+				lexer.Token{Type: TName, Value: "one"},
+				lexer.Token{Type: TPredicateStart, Value: "["},
+				lexer.Token{Type: TNumber, Value: ""},
+				lexer.Token{Type: TRange, Value: ":"},
+				lexer.Token{Type: TNumber, Value: "3"},
+				lexer.Token{Type: TPredicateEnd, Value: "]"},
+			},
+		},
+		{
+			path: "$.one[3:]",
+			tokens: []lexer.Token{
+				lexer.Token{Type: TAbsolute, Value: "$"},
+				lexer.Token{Type: TChildDot, Value: "."},
+				lexer.Token{Type: TName, Value: "one"},
+				lexer.Token{Type: TPredicateStart, Value: "["},
+				lexer.Token{Type: TNumber, Value: "3"},
+				lexer.Token{Type: TRange, Value: ":"},
+				lexer.Token{Type: TNumber, Value: ""},
+				lexer.Token{Type: TPredicateEnd, Value: "]"},
+			},
+		},
+		{
+			path: "$..one",
+			tokens: []lexer.Token{
+				lexer.Token{Type: TAbsolute, Value: "$"},
+				lexer.Token{Type: TRecursive, Value: "."},
+				lexer.Token{Type: TChildDot, Value: "."},
+				lexer.Token{Type: TName, Value: "one"},
+			},
+		},
+		{
+			path: "$['one']",
+			tokens: []lexer.Token{
+				lexer.Token{Type: TAbsolute, Value: "$"},
+				lexer.Token{Type: TChildStart, Value: "["},
+				lexer.Token{Type: TQuotedName, Value: "'one'"},
+				lexer.Token{Type: TChildEnd, Value: "]"},
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Log("testing path: ", tt.path)
+		l := lexer.New(tt.path, pathState)
+		l.Start()
+
+		func() {
+			for i, expected := range tt.tokens {
+				actual, done := l.NextToken()
+				if done || actual == nil {
+					t.Errorf("Lexer(%q) finished early, expecting %v", tt.path, expected)
+					return
+				}
+				if actual.Type != expected.Type {
+					t.Errorf("Lexer(%q) token %d => %s, expected %s", tt.path, i, tokenNames[actual.Type], tokenNames[expected.Type])
+					return
+				}
+				if actual.Value != expected.Value {
+					t.Errorf("Lexer(%q) token %d =>  %v, expected %v", tt.path, i, actual, expected)
+					return
+				}
+			}
+		}()
+	}
+}