Java tutorial
/** * Copyright (c) 2009-2011, The HATS Consortium. All rights reserved. * This file is licensed under the terms of the Modified BSD License. */ package abs.backend.erlang; import static org.junit.Assert.assertEquals; import java.io.BufferedReader; import java.io.File; import java.io.IOException; import java.io.InputStreamReader; import java.nio.charset.Charset; import java.util.regex.Matcher; import org.apache.commons.io.FileUtils; import org.junit.Assert; import org.junit.Assume; import abs.ABSTest; import abs.backend.BackendTestDriver; import abs.backend.common.SemanticTests; import abs.frontend.ast.*; import com.google.common.io.Files; public class ErlangTestDriver extends ABSTest implements BackendTestDriver { @Override public String toString() { return "Erlang"; } public static boolean checkErlang() { if (SemanticTests.checkProg("erl")) { // http://stackoverflow.com/a/9561398/60462 ProcessBuilder pb = new ProcessBuilder("erl", "-eval", "erlang:display(erlang:system_info(otp_release)), halt().", "-noshell"); try { Process p = pb.start(); InputStreamReader r = new InputStreamReader(p.getInputStream()); BufferedReader b = new BufferedReader(r); Assert.assertEquals(0, p.waitFor()); String version = b.readLine(); java.util.regex.Pattern pat = java.util.regex.Pattern.compile("\"(\\d*).*"); Matcher m = pat.matcher(version); Assert.assertTrue("Could not identify Erlang version: " + version, m.matches()); String v = m.group(1); Assume.assumeTrue("Need Erlang R17 or better.", Integer.parseInt(v) >= 17); } catch (IOException e) { return false; } catch (InterruptedException e) { return false; } } return true; } @Override public void assertEvalEquals(String absCode, boolean value) throws Exception { if (value) assertEvalTrue(absCode); else assertEvalFails(absCode); } @Override public void assertEvalFails(String absCode) throws Exception { Assert.assertEquals(null, runAndCheck(absCode)); } @Override public void assertEvalTrue(String absCode) throws Exception { Assert.assertEquals("true", runAndCheck(absCode)); } /** * Parses, complies, runs given code and returns value of testresult. * * @param absCode * @return either the Result, or if an execution error occurred null */ private String runAndCheck(String absCode) throws Exception { File f = null; try { f = Files.createTempDir(); f.deleteOnExit(); Model model = assertParseOk(absCode, Config.WITH_STD_LIB, Config.TYPE_CHECK, /* XXX:CI Config.WITH_LOC_INF, */ Config.WITHOUT_MODULE_NAME); String mainModule = genCode(model, f, true); make(f); return run(f, mainModule); } finally { try { FileUtils.deleteDirectory(f); } catch (IOException e) { // Ignore Ex, File should be deleted anyway } } } public void generateAndCompile(Model model) throws Exception { File f = null; try { f = Files.createTempDir(); f.deleteOnExit(); genCode(model, f, false); make(f); } finally { try { FileUtils.deleteDirectory(f); } catch (IOException e) { // Ignore Ex, File should be deleted anyway } } } /** * Generates Erlang code in target directory * * To retrieve the testresult value, we inject in the mainblock a return * statement, which will then be the result of the execution * * @return the Module Name, which contains the Main Block * */ private String genCode(Model model, File targetDir, boolean appendResultprinter) throws IOException, InterruptedException { if (model.hasErrors()) { Assert.fail(model.getErrors().getFirst().getHelpMessage()); } if (model.hasTypeErrors()) { Assert.fail(model.getTypeErrors().getFirst().getHelpMessage()); } MainBlock mb = model.getMainBlock(); if (mb != null && appendResultprinter) { mb.addStmt(new ReturnStmt(new List<Annotation>(), new VarUse("testresult"))); } ErlangBackend.compile(model, targetDir); if (mb == null) return null; else return mb.getModuleDecl().getName(); } /** * Complies code in workDir */ private void make(File workDir) throws Exception { ProcessBuilder pb = new ProcessBuilder("erl", "-pa", "ebin", "-noshell", "-noinput", "-eval", "case make:all() of up_to_date -> halt(0); _ -> halt(1) end."); pb.directory(workDir); pb.inheritIO(); Process p = pb.start(); Assert.assertEquals("Compile failed", 0, p.waitFor()); } private static final String RUN_SCRIPT = "#!/usr/bin/env escript\n" + "%%! -pa ebin\n" + "main(Arg)->" + "V=runtime:start(Arg)," + "timer:sleep(10)," + "io:format(\"RES=~p~n\",[V])."; /** * Executes mainModule * * We replace the run script by a new version, which will write the Result * to STDOUT Furthermore to detect faults, we have a Timeout process, which * will kill the runtime system after 2 seconds */ private String run(File workDir, String mainModule) throws Exception { String val = null; File runFile = new File(workDir, "run"); Files.write(RUN_SCRIPT, runFile, Charset.forName("UTF-8")); runFile.setExecutable(true); ProcessBuilder pb = new ProcessBuilder(runFile.getAbsolutePath(), mainModule); pb.directory(workDir); pb.redirectErrorStream(true); Process p = pb.start(); Thread t = new Thread(new TimeoutThread(p)); t.start(); // Search for result BufferedReader br = new BufferedReader(new InputStreamReader(p.getInputStream())); while (true) { String line = br.readLine(); if (line == null) break; if (line.startsWith("RES=")) val = line.split("=")[1]; } int res = p.waitFor(); t.interrupt(); if (res != 0) return null; return val; } @Override public void assertEvalTrue(Model model) throws Exception { File f = null; try { f = Files.createTempDir(); f.deleteOnExit(); String mainModule = genCode(model, f, true); make(f); assertEquals("true", run(f, mainModule)); } finally { try { FileUtils.deleteDirectory(f); } catch (IOException e) { // Ignore Ex, File should be deleted anyway } } } } class TimeoutThread implements Runnable { private final Process p; public TimeoutThread(Process p) { super(); this.p = p; } @Override public void run() { try { Thread.sleep(2000); p.destroy(); } catch (InterruptedException e) { } } }