Semver version (#272)

* semver version

* add test

Author: xufulin1994

src/grammar/base.pegjs

@@ -35,7 +35,10 @@ description = "\"" _ inner:(!"\"" i:. {return i})* "\"" {
 }
 
 // version
-semver = semver:([0-9]+ "." [0-9]+ "." [0-9]+ ("-" [a-zA-Z0-9.-]+)?) { return semver.flat(2).join(""); }
+semver = semver:([0-9]+ "." [0-9]+ "." [0-9]+ preRelease) { return semver.flat(Infinity).join(""); }
+preRelease = ('-' preReleaseIdentifiers)?;
+preReleaseIdentifiers = identifier ('.' [0-9a-zA-Z-]+)*;
+identifier = [a-zA-Z-] ([a-zA-Z-] / [0-9])*;
 
 // whitespace or comment
 _  = ([ \t\r\n]+ / comment)*

src/tests/semver.test.ts

@@ -0,0 +1,50 @@
+import {readFile} from "../parse";
+import peg from "pegjs";
+import * as path from "path";
+
+const grammar = readFile(path.resolve(__dirname, '..'), "grammar", "base.pegjs")
+
+const parser = peg.generate(grammar, {allowedStartRules: ["semver"]});
+
+
+describe("semver", () => {
+    it("should parse a semantic version with a pre-release identifier", () => {
+        const input_1 = "1.2.3-alpha";
+        const expected_1 = "1.2.3-alpha";
+
+        const input_2 = "1.0.0-alpha.beta";
+        const expected_2 = "1.0.0-alpha.beta";
+
+        const input_3 = "1.2.3----RC-SNAPSHOT.12.9.1--.12";
+        const expected_3 = "1.2.3----RC-SNAPSHOT.12.9.1--.12";
+        // Parse the input string
+        const result_1 = parser.parse(input_1);
+        const result_2 = parser.parse(input_2);
+        const result_3 = parser.parse(input_3);
+
+        // Check the result
+        expect(result_1).toBe(expected_1);
+        expect(result_2).toBe(expected_2);
+        expect(result_3).toBe(expected_3);
+    });
+
+    it("should parse a semantic version with no pre-release identifier", () => {
+        const input = "1.2.3";
+        const expected = "1.2.3";
+
+        // Parse the input string
+        const result = parser.parse(input);
+
+        // Check the result
+        expect(result).toBe(expected);
+    });
+
+    it("parse a invalid semantic version throw error", () => {
+        const input_1 = "1.2.3-0123";
+        const input_2 = "alpha_beta";
+
+        // Parsing an invalid semantic version should throw an error
+        expect(() => parser.parse(input_1)).toThrow();
+        expect(() => parser.parse(input_2)).toThrow();
+    });
+});