svg-tools/tests/document/source-parser.test.ts

import { describe, expect, it } from "vitest";
import { defaultSvgLimits } from "../../src/app/limits";
import { parseSvgSource } from "../../src/document/source-parser";
import {
  applySourcePatches,
  patchAttribute,
} from "../../src/document/source-patcher";

const source = `<?xml version="1.0"?>
<!--preserve me-->
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 80">
  <vendor:thing xmlns:vendor="urn:vendor" unusual="yes"><circle id="dot" cx="10" cy="20" r="4"/></vendor:thing>
</svg>`;

describe("source-faithful SVG parsing", () => {
  it("retains canonical source and maps unknown elements to exact ranges", () => {
    const result = parseSvgSource(source, 7);
    expect(result.valid).toBe(true);
    expect(result.semantic?.source).toBe(source);
    expect(result.semantic?.revision).toBe(7);
    const vendor = [...result.semantic!.nodes.values()].find(
      (node) => node.name === "vendor:thing",
    )!;
    expect(
      source.slice(vendor.sourceRange.full.from, vendor.sourceRange.full.to),
    ).toContain("vendor:thing");
    expect(vendor.attributes.unusual).toBe("yes");
  });

  it("rejects malformed XML without constructing a semantic model", () => {
    const result = parseSvgSource(
      '<svg xmlns="http://www.w3.org/2000/svg"><g>',
      2,
    );
    expect(result.valid).toBe(false);
    expect(result.semantic).toBeNull();
    expect(result.diagnostics.some((item) => item.severity === "error")).toBe(
      true,
    );
    expect(result.diagnostics).toContainEqual(
      expect.objectContaining({ code: "xml-unclosed-element" }),
    );
  });

  it("preserves but refuses entity declarations before invoking the XML parser", () => {
    const entitySource = `<!DOCTYPE svg [<!ENTITY local "blocked">]><svg xmlns="http://www.w3.org/2000/svg"><text>&local;</text></svg>`;
    const result = parseSvgSource(entitySource, 8);

    expect(result.valid).toBe(false);
    expect(result.semantic).toBeNull();
    expect(result.source).toBe(entitySource);
    expect(result.diagnostics).toContainEqual(
      expect.objectContaining({
        code: "entity-declaration-blocked",
        severity: "error",
      }),
    );
  });

  it("preserves a simple doctype while excluding it from the editing parser", () => {
    const doctypeSource = `<!DOCTYPE svg SYSTEM "https://invalid.example/svg.dtd"><svg xmlns="http://www.w3.org/2000/svg"><rect width="2" height="3"/></svg>`;
    const result = parseSvgSource(doctypeSource, 9);

    expect(result.valid).toBe(true);
    expect(result.semantic?.source).toBe(doctypeSource);
    expect(result.diagnostics).toContainEqual(
      expect.objectContaining({
        code: "doctype-preserved",
        severity: "warning",
      }),
    );
  });

  it("treats duplicate IDs as editable diagnostics, not XML invalidity", () => {
    const result = parseSvgSource(
      '<svg xmlns="http://www.w3.org/2000/svg"><g id="same"/><path id="same" d="M0 0L1 1"/></svg>',
      3,
    );
    expect(result.valid).toBe(true);
    expect(result.semantic).not.toBeNull();
    expect(result.diagnostics).toContainEqual(
      expect.objectContaining({ code: "duplicate-id", severity: "warning" }),
    );
  });

  it("patches one attribute while preserving comments, quote style and unknown content", () => {
    const result = parseSvgSource(source, 1);
    const dot = [...result.semantic!.nodes.values()].find(
      (node) => node.id === "dot",
    )!;
    const patch = patchAttribute(source, dot, "cx", "42", result.preferences)!;
    const next = applySourcePatches(source, [patch]);
    expect(next).toBe(source.replace('cx="10"', 'cx="42"'));
    expect(next).toContain("<!--preserve me-->");
    expect(next).toContain("vendor:thing");
  });

  it("rejects overlapping or stale patches", () => {
    expect(() =>
      applySourcePatches("abcdef", [
        { from: 1, to: 4, insert: "x", label: "first" },
        { from: 3, to: 5, insert: "y", label: "second" },
      ]),
    ).toThrow(/overlapping/u);
  });

  it("enforces each configurable structural resource limit", () => {
    const constrained = {
      ...defaultSvgLimits,
      maximumAttributeLength: 12,
      maximumPathCommandsPerPath: 2,
      maximumPathCommandsTotal: 2,
      maximumCssRules: 1,
      maximumReferences: 0,
      maximumAnimations: 0,
      maximumFilterPrimitives: 0,
      maximumTextLength: 4,
      maximumEmbeddedResourceBytes: 8,
    };
    const result = parseSvgSource(
      `<svg xmlns="http://www.w3.org/2000/svg">
        <style>.a{fill:red}.b{stroke:blue}</style>
        <defs><filter id="fx"><feGaussianBlur stdDeviation="1"/></filter></defs>
        <path d="M0 0L1 1L2 2" filter="url(#fx)"/>
        <image href="data:image/png;base64,AAAAAAAAAAAA"/>
        <animate attributeName="opacity" values="0;1"/>
        <text>longer text</text>
      </svg>`,
      9,
      constrained,
    );
    const codes = result.diagnostics.map((item) => item.code);
    expect(result.valid).toBe(false);
    expect(codes).toEqual(
      expect.arrayContaining([
        "attribute-length-limit",
        "embedded-resource-limit",
        "path-command-per-element-limit",
        "path-command-limit",
        "css-rule-limit",
        "reference-limit",
        "animation-limit",
        "filter-primitive-limit",
        "text-length-limit",
        "total-text-limit",
      ]),
    );
  });

  it("counts SVG path commands without mistaking exponent notation for commands", () => {
    const result = parseSvgSource(
      '<svg xmlns="http://www.w3.org/2000/svg"><path d="M1e2 0L2e2 1"/></svg>',
      4,
    );
    expect(result.semantic?.metrics.pathCommandCount).toBe(2);
  });

  it("counts implicit path groups and packed arc flags as resolved commands", () => {
    const result = parseSvgSource(
      '<svg xmlns="http://www.w3.org/2000/svg"><path d="M0 0 1 1 2 2 A5 6 0 0110 20"/></svg>',
      5,
      { ...defaultSvgLimits, maximumPathCommandsPerPath: 3 },
    );

    expect(result.semantic?.metrics.pathCommandCount).toBe(4);
    expect(result.diagnostics).toContainEqual(
      expect.objectContaining({ code: "path-command-per-element-limit" }),
    );
  });
});