Final Toml-Path Solution

* Refactored type names and file names to mesh with existing TOML library more closely
* Added QueryResult structure that provides values and position data
* Added Query() method to TomlTree type
* Tests, tests, and more tests
* Fixed bug where positions returned from some tables were invalid
* Added test case for bug patch

The bugfix was an interesting case. Position information wasn't being
set in cases where createPath was called.  So table names like [foo.bar]
would result in table 'foo' having no position.

querylexer_test.go

@@ -0,0 +1,97 @@
+package toml
+
+import (
+	"testing"
+)
+
+func testQLFlow(t *testing.T, input string, expectedFlow []token) {
+	ch := lexQuery(input)
+	for idx, expected := range expectedFlow {
+		token := <-ch
+		if token != expected {
+			t.Log("While testing #", idx, ":", input)
+			t.Log("compared", token, "to", expected)
+			t.Log(token.val, "<->", expected.val)
+			t.Log(token.typ, "<->", expected.typ)
+			t.Log(token.Line, "<->", expected.Line)
+			t.Log(token.Col, "<->", expected.Col)
+			t.FailNow()
+		}
+	}
+
+	tok, ok := <-ch
+	if ok {
+		t.Log("channel is not closed!")
+		t.Log(len(ch)+1, "tokens remaining:")
+
+		t.Log("token ->", tok)
+		for token := range ch {
+			t.Log("token ->", token)
+		}
+		t.FailNow()
+	}
+}
+
+func TestLexSpecialChars(t *testing.T) {
+	testQLFlow(t, " .$[]..()?*", []token{
+		token{Position{1, 2}, tokenDot, "."},
+		token{Position{1, 3}, tokenDollar, "$"},
+		token{Position{1, 4}, tokenLeftBracket, "["},
+		token{Position{1, 5}, tokenRightBracket, "]"},
+		token{Position{1, 6}, tokenDotDot, ".."},
+		token{Position{1, 8}, tokenLeftParen, "("},
+		token{Position{1, 9}, tokenRightParen, ")"},
+		token{Position{1, 10}, tokenQuestion, "?"},
+		token{Position{1, 11}, tokenStar, "*"},
+		token{Position{1, 12}, tokenEOF, ""},
+	})
+}
+
+func TestLexString(t *testing.T) {
+	testQLFlow(t, "'foo'", []token{
+		token{Position{1, 2}, tokenString, "foo"},
+		token{Position{1, 6}, tokenEOF, ""},
+	})
+}
+
+func TestLexDoubleString(t *testing.T) {
+	testQLFlow(t, `"bar"`, []token{
+		token{Position{1, 2}, tokenString, "bar"},
+		token{Position{1, 6}, tokenEOF, ""},
+	})
+}
+
+func TestLexKey(t *testing.T) {
+	testQLFlow(t, "foo", []token{
+		token{Position{1, 1}, tokenKey, "foo"},
+		token{Position{1, 4}, tokenEOF, ""},
+	})
+}
+
+func TestLexRecurse(t *testing.T) {
+	testQLFlow(t, "$..*", []token{
+		token{Position{1, 1}, tokenDollar, "$"},
+		token{Position{1, 2}, tokenDotDot, ".."},
+		token{Position{1, 4}, tokenStar, "*"},
+		token{Position{1, 5}, tokenEOF, ""},
+	})
+}
+
+func TestLexBracketKey(t *testing.T) {
+	testQLFlow(t, "$[foo]", []token{
+		token{Position{1, 1}, tokenDollar, "$"},
+		token{Position{1, 2}, tokenLeftBracket, "["},
+		token{Position{1, 3}, tokenKey, "foo"},
+		token{Position{1, 6}, tokenRightBracket, "]"},
+		token{Position{1, 7}, tokenEOF, ""},
+	})
+}
+
+func TestLexSpace(t *testing.T) {
+	testQLFlow(t, "foo bar baz", []token{
+		token{Position{1, 1}, tokenKey, "foo"},
+		token{Position{1, 5}, tokenKey, "bar"},
+		token{Position{1, 9}, tokenKey, "baz"},
+		token{Position{1, 12}, tokenEOF, ""},
+	})
+}