generateFileCoverageHtml.ts

import * as path from "node:path";
import { oneLine } from "common-tags";
import { FileCoverageMode } from "../inputs/FileCoverageMode";
import type { JsonFinal } from "../types/JsonFinal";
import type { JsonSummary } from "../types/JsonSummary";
import { generateBlobFileUrl } from "./generateFileUrl";
import {
	type LineRange,
	getUncoveredLinesFromStatements,
} from "./getUncoveredLinesFromStatements";

type FileCoverageInputs = {
	jsonSummary: JsonSummary;
	jsonFinal: JsonFinal;
	fileCoverageMode: FileCoverageMode;
	pullChanges: string[];
	commitSHA: string;
};

const workspacePath = process.cwd();
const generateFileCoverageHtml = ({
	jsonSummary,
	jsonFinal,
	fileCoverageMode,
	pullChanges,
	commitSHA,
}: FileCoverageInputs) => {
	const filePaths = Object.keys(jsonSummary).filter((key) => key !== "total");

	const formatFileLine = (filePath: string) => {
		const coverageSummary = jsonSummary[filePath];
		const lineCoverage = jsonFinal[filePath];

		// LineCoverage might be empty if coverage-final.json was not provided.
		const uncoveredLines = lineCoverage
			? getUncoveredLinesFromStatements(jsonFinal[filePath])
			: [];
		const relativeFilePath = path.relative(workspacePath, filePath);
		const url = generateBlobFileUrl(relativeFilePath, commitSHA);

		return `
      <tr>
        <td align="left"><a href="${url}">${relativeFilePath}</a></td>
        <td align="right">${coverageSummary.statements.pct}%</td>
        <td align="right">${coverageSummary.branches.pct}%</td>
        <td align="right">${coverageSummary.functions.pct}%</td>
        <td align="right">${coverageSummary.lines.pct}%</td>
        <td align="left">${createRangeURLs(uncoveredLines, url)}</td>
      </tr>`;
	};

	let reportData = "";

	const [changedFiles, unchangedFiles] = splitFilesByChangeStatus(
		filePaths,
		pullChanges,
	);

	if (
		fileCoverageMode === FileCoverageMode.Changes &&
		changedFiles.length === 0
	) {
		return "No changed files found.";
	}

	if (changedFiles.length > 0) {
		reportData += `
			${formatGroupLine("Changed Files")} 
			${changedFiles.map(formatFileLine).join("")}
		`;
	}

	if (fileCoverageMode === FileCoverageMode.All && unchangedFiles.length > 0) {
		reportData += `
			${formatGroupLine("Unchanged Files")}
			${unchangedFiles.map(formatFileLine).join("")}
		`;
	}

	return oneLine`
    <table>
      <thead>
        <tr>
         <th align="left">File</th>
         <th align="right">Stmts</th>
         <th align="right">% Branch</th>
         <th align="right">% Funcs</th>
         <th align="right">% Lines</th>
         <th align="left">Uncovered Lines</th>
        </tr>
      </thead>
      <tbody>
      ${reportData}
      </tbody>
    </table>
  `;
};

function formatGroupLine(caption: string): string {
	return `
		<tr>
			<td align="left" colspan="6"><b>${caption}</b></td>
		</tr>
	`;
}

function createRangeURLs(uncoveredLines: LineRange[], url: string): string {
	return uncoveredLines
		.map((range) => {
			let linkText = `${range.start}`;
			let urlHash = `#L${range.start}`;

			if (range.start !== range.end) {
				linkText += `-${range.end}`;
				urlHash += `-L${range.end}`;
			}

			return `<a href="${url}${urlHash}" class="text-red">${linkText}</a>`;
		})
		.join(", ");
}

function splitFilesByChangeStatus(
	filePaths: string[],
	pullChanges: string[],
): [string[], string[]] {
	return filePaths.reduce(
		([changedFiles, unchangedFiles], filePath) => {
			// Pull Changes has filePaths relative to the git repository, whereas the jsonSummary has filePaths relative to the workspace.
			// So we have to convert the filePaths to be relative to the workspace.
			const comparePath = path.relative(workspacePath, filePath);
			if (pullChanges.includes(comparePath)) {
				changedFiles.push(filePath);
			} else {
				unchangedFiles.push(filePath);
			}
			return [changedFiles, unchangedFiles];
		},
		[[], []] as [string[], string[]],
	);
}

export { generateFileCoverageHtml };