export function runTool()

in src/util.ts [759:859]
92 lines of code
28 McCabe index (conditional complexity)

export function runTool(
	args: string[],
	cwd: string,
	severity: string,
	useStdErr: boolean,
	toolName: string,
	env: any,
	printUnexpectedOutput: boolean,
	token?: vscode.CancellationToken
): Promise<ICheckResult[]> {
	let cmd: string;
	if (toolName) {
		cmd = getBinPath(toolName);
	} else {
		const goRuntimePath = getBinPath('go');
		if (!goRuntimePath) {
			return Promise.reject(new Error('Cannot find "go" binary. Update PATH or GOROOT appropriately'));
		}
		cmd = goRuntimePath;
	}

	let p: cp.ChildProcess;
	if (token) {
		token.onCancellationRequested(() => {
			if (p) {
				killProcessTree(p);
			}
		});
	}
	cwd = fixDriveCasingInWindows(cwd);
	return new Promise((resolve, reject) => {
		p = cp.execFile(cmd, args, { env, cwd }, (err, stdout, stderr) => {
			try {
				if (err && (<any>err).code === 'ENOENT') {
					// Since the tool is run on save which can be frequent
					// we avoid sending explicit notification if tool is missing
					console.log(`Cannot find ${toolName ? toolName : 'go'}`);
					return resolve([]);
				}
				if (err && stderr && !useStdErr) {
					outputChannel.appendLine(['Error while running tool:', cmd, ...args].join(' '));
					outputChannel.appendLine(stderr);
					return resolve([]);
				}
				const lines = (useStdErr ? stderr : stdout).toString().split('\n');
				outputChannel.appendLine([cwd + '>Finished running tool:', cmd, ...args].join(' '));

				const ret: ICheckResult[] = [];
				let unexpectedOutput = false;
				let atLeastSingleMatch = false;
				for (const l of lines) {
					if (l[0] === '\t' && ret.length > 0) {
						ret[ret.length - 1].msg += '\n' + l;
						continue;
					}
					const match = /^([^:]*: )?((.:)?[^:]*):(\d+)(:(\d+)?)?:(?:\w+:)? (.*)$/.exec(l);
					if (!match) {
						if (printUnexpectedOutput && useStdErr && stderr) {
							unexpectedOutput = true;
						}
						continue;
					}
					atLeastSingleMatch = true;
					const [, , file, , lineStr, , colStr, msg] = match;
					const line = +lineStr;
					const col = colStr ? +colStr : undefined;

					// Building skips vendor folders,
					// But vet and lint take in directories and not import paths, so no way to skip them
					// So prune out the results from vendor folders here.
					if (
						!path.isAbsolute(file) &&
						(file.startsWith(`vendor${path.sep}`) || file.indexOf(`${path.sep}vendor${path.sep}`) > -1)
					) {
						continue;
					}

					const filePath = path.resolve(cwd, file);
					ret.push({ file: filePath, line, col, msg, severity });
					outputChannel.appendLine(`${filePath}:${line}:${col ?? ''} ${msg}`);
				}
				if (!atLeastSingleMatch && unexpectedOutput && vscode.window.activeTextEditor) {
					outputChannel.appendLine(stderr);
					if (err) {
						ret.push({
							file: vscode.window.activeTextEditor.document.fileName,
							line: 1,
							col: 1,
							msg: stderr,
							severity: 'error'
						});
					}
				}
				outputChannel.appendLine('');
				resolve(ret);
			} catch (e) {
				reject(e);
			}
		});
	});
}