Notes/spec/search/lexer.spec.ts

import lex from "../../src/services/search/services/lex.js";

describe("Lexer fulltext", () => {
    it("simple lexing", () => {
        expect(lex("hello world").fulltextTokens.map((t) => t.token)).toEqual(["hello", "world"]);

        expect(lex("hello, world").fulltextTokens.map((t) => t.token)).toEqual(["hello", "world"]);
    });

    it("use quotes to keep words together", () => {
        expect(lex("'hello world' my friend").fulltextTokens.map((t) => t.token)).toEqual(["hello world", "my", "friend"]);

        expect(lex('"hello world" my friend').fulltextTokens.map((t) => t.token)).toEqual(["hello world", "my", "friend"]);

        expect(lex("`hello world` my friend").fulltextTokens.map((t) => t.token)).toEqual(["hello world", "my", "friend"]);
    });

    it("you can use different quotes and other special characters inside quotes", () => {
        expect(lex("'i can use \" or ` or #~=*' without problem").fulltextTokens.map((t) => t.token)).toEqual(['i can use " or ` or #~=*', "without", "problem"]);
    });

    it("I can use backslash to escape quotes", () => {
        expect(lex('hello \\"world\\"').fulltextTokens.map((t) => t.token)).toEqual(["hello", '"world"']);

        expect(lex("hello \\'world\\'").fulltextTokens.map((t) => t.token)).toEqual(["hello", "'world'"]);

        expect(lex("hello \\`world\\`").fulltextTokens.map((t) => t.token)).toEqual(["hello", "`world`"]);

        expect(lex('"hello \\"world\\"').fulltextTokens.map((t) => t.token)).toEqual(['hello "world"']);

        expect(lex("'hello \\'world\\''").fulltextTokens.map((t) => t.token)).toEqual(["hello 'world'"]);

        expect(lex("`hello \\`world\\``").fulltextTokens.map((t) => t.token)).toEqual(["hello `world`"]);

        expect(lex("\\#token").fulltextTokens.map((t) => t.token)).toEqual(["#token"]);
    });

    it("quote inside a word does not have a special meaning", () => {
        const lexResult = lex("d'Artagnan is dead #hero = d'Artagnan");

        expect(lexResult.fulltextTokens.map((t) => t.token)).toEqual(["d'artagnan", "is", "dead"]);

        expect(lexResult.expressionTokens.map((t) => t.token)).toEqual(["#hero", "=", "d'artagnan"]);
    });

    it("if quote is not ended then it's just one long token", () => {
        expect(lex("'unfinished quote").fulltextTokens.map((t) => t.token)).toEqual(["unfinished quote"]);
    });

    it("parenthesis and symbols in fulltext section are just normal characters", () => {
        expect(lex("what's u=p <b(r*t)h>").fulltextTokens.map((t) => t.token)).toEqual(["what's", "u=p", "<b(r*t)h>"]);
    });

    it("operator characters in expressions are separate tokens", () => {
        expect(lex("# abc+=-def**-+d").expressionTokens.map((t) => t.token)).toEqual(["#", "abc", "+=-", "def", "**-+", "d"]);
    });

    it("escaping special characters", () => {
        expect(lex("hello \\#\\~\\'").fulltextTokens.map((t) => t.token)).toEqual(["hello", "#~'"]);
    });
});

describe("Lexer expression", () => {
    it("simple attribute existence", () => {
        expect(lex("#label ~relation").expressionTokens.map((t) => t.token)).toEqual(["#label", "~relation"]);
    });

    it("simple label operators", () => {
        expect(lex("#label*=*text").expressionTokens.map((t) => t.token)).toEqual(["#label", "*=*", "text"]);
    });

    it("simple label operator with in quotes", () => {
        expect(lex("#label*=*'text'").expressionTokens).toEqual([
            { token: "#label", inQuotes: false, startIndex: 0, endIndex: 5 },
            { token: "*=*", inQuotes: false, startIndex: 6, endIndex: 8 },
            { token: "text", inQuotes: true, startIndex: 10, endIndex: 13 }
        ]);
    });

    it("simple label operator with param without quotes", () => {
        expect(lex("#label*=*text").expressionTokens).toEqual([
            { token: "#label", inQuotes: false, startIndex: 0, endIndex: 5 },
            { token: "*=*", inQuotes: false, startIndex: 6, endIndex: 8 },
            { token: "text", inQuotes: false, startIndex: 9, endIndex: 12 }
        ]);
    });

    it("simple label operator with empty string param", () => {
        expect(lex("#label = ''").expressionTokens).toEqual([
            { token: "#label", inQuotes: false, startIndex: 0, endIndex: 5 },
            { token: "=", inQuotes: false, startIndex: 7, endIndex: 7 },
            // weird case for empty strings which ends up with endIndex < startIndex :-(
            { token: "", inQuotes: true, startIndex: 10, endIndex: 9 }
        ]);
    });

    it("note. prefix also separates fulltext from expression", () => {
        expect(lex(`hello fulltext note.labels.capital = Prague`).expressionTokens.map((t) => t.token)).toEqual(["note", ".", "labels", ".", "capital", "=", "prague"]);
    });

    it("note. prefix in quotes will note start expression", () => {
        expect(lex(`hello fulltext "note.txt"`).expressionTokens.map((t) => t.token)).toEqual([]);

        expect(lex(`hello fulltext "note.txt"`).fulltextTokens.map((t) => t.token)).toEqual(["hello", "fulltext", "note.txt"]);
    });

    it("complex expressions with and, or and parenthesis", () => {
        expect(lex(`# (#label=text OR #second=text) AND ~relation`).expressionTokens.map((t) => t.token)).toEqual([
            "#",
            "(",
            "#label",
            "=",
            "text",
            "or",
            "#second",
            "=",
            "text",
            ")",
            "and",
            "~relation"
        ]);
    });

    it("dot separated properties", () => {
        expect(lex(`# ~author.title = 'Hugh Howey' AND note.'book title' = 'Silo'`).expressionTokens.map((t) => t.token)).toEqual([
            "#",
            "~author",
            ".",
            "title",
            "=",
            "hugh howey",
            "and",
            "note",
            ".",
            "book title",
            "=",
            "silo"
        ]);
    });

    it("negation of label and relation", () => {
        expect(lex(`#!capital ~!neighbor`).expressionTokens.map((t) => t.token)).toEqual(["#!capital", "~!neighbor"]);
    });

    it("negation of sub-expression", () => {
        expect(lex(`# not(#capital) and note.noteId != "root"`).expressionTokens.map((t) => t.token)).toEqual(["#", "not", "(", "#capital", ")", "and", "note", ".", "noteid", "!=", "root"]);
    });

    it("order by multiple labels", () => {
        expect(lex(`# orderby #a,#b`).expressionTokens.map((t) => t.token)).toEqual(["#", "orderby", "#a", ",", "#b"]);
    });
});

describe("Lexer invalid queries and edge cases", () => {
    it("concatenated attributes", () => {
        expect(lex("#label~relation").expressionTokens.map((t) => t.token)).toEqual(["#label", "~relation"]);
    });

    it("trailing escape \\", () => {
        expect(lex("abc \\").fulltextTokens.map((t) => t.token)).toEqual(["abc", "\\"]);
    });
});