Properly handle directories as arguments (#713)

* fix(cat): do not cat directories

Fixes #707

* fix(head): do not let head() read directories

Also fixes a typo

* fix(sort): do not sort directories

Also fixes a typo

* fix(tail): do not let tail() read directories

Also fixes a typo

* fix(uniq): do not let uniq() read directories

We also had a test which called sort() instead of uniq(), so we never
actually tested the missing-file case. This fixes that as well.

This also throws an error for using a directory as output.

* fix(pipe): fix breakages with piped commands

src/cat.js

@@ -30,6 +30,8 @@ function _cat(options, files) {
   files.forEach(function (file) {
     if (!fs.existsSync(file)) {
       common.error('no such file or directory: ' + file);
+    } else if (fs.statSync(file).isDirectory()) {
+      common.error(file + ': Is a directory');
     }
 
     cat += fs.readFileSync(file, 'utf8');

src/head.js

@@ -72,9 +72,16 @@ function _head(options, files) {
 
   var shouldAppendNewline = false;
   files.forEach(function (file) {
-    if (!fs.existsSync(file) && file !== '-') {
-      common.error('no such file or directory: ' + file, { continue: true });
-      return;
+    if (file !== '-') {
+      if (!fs.existsSync(file)) {
+        common.error('no such file or directory: ' + file, { continue: true });
+        return;
+      } else if (fs.statSync(file).isDirectory()) {
+        common.error("error reading '" + file + "': Is a directory", {
+          continue: true,
+        });
+        return;
+      }
     }
 
     var contents;

src/sort.js

@@ -69,9 +69,16 @@ function _sort(options, files) {
 
   var lines = [];
   files.forEach(function (file) {
-    if (!fs.existsSync(file) && file !== '-') {
-      // exit upon any sort of error
-      common.error('no such file or directory: ' + file);
+    if (file !== '-') {
+      if (!fs.existsSync(file)) {
+        common.error('no such file or directory: ' + file, { continue: true });
+        return;
+      } else if (fs.statSync(file).isDirectory()) {
+        common.error('read failed: ' + file + ': Is a directory', {
+          continue: true,
+        });
+        return;
+      }
     }
 
     var contents = file === '-' ? pipe : fs.readFileSync(file, 'utf8');

src/tail.js

@@ -46,9 +46,16 @@ function _tail(options, files) {
 
   var shouldAppendNewline = false;
   files.forEach(function (file) {
-    if (!fs.existsSync(file) && file !== '-') {
-      common.error('no such file or directory: ' + file, { continue: true });
-      return;
+    if (file !== '-') {
+      if (!fs.existsSync(file)) {
+        common.error('no such file or directory: ' + file, { continue: true });
+        return;
+      } else if (fs.statSync(file).isDirectory()) {
+        common.error("error reading '" + file + "': Is a directory", {
+          continue: true,
+        });
+        return;
+      }
     }
 
     var contents = file === '-' ? pipe : fs.readFileSync(file, 'utf8');

src/uniq.js

@@ -40,7 +40,18 @@ function _uniq(options, input, output) {
   // Check if this is coming from a pipe
   var pipe = common.readFromPipe();
 
-  if (!input && !pipe) common.error('no input given');
+  if (!pipe) {
+    if (!input) common.error('no input given');
+
+    if (!fs.existsSync(input)) {
+      common.error(input + ': No such file or directory');
+    } else if (fs.statSync(input).isDirectory()) {
+      common.error("error reading '" + input + "'");
+    }
+  }
+  if (output && fs.existsSync(output) && fs.statSync(output).isDirectory()) {
+    common.error(output + ': Is a directory');
+  }
 
   var lines = (input ? fs.readFileSync(input, 'utf8') : pipe).
               trimRight().

test/cat.js

@@ -25,6 +25,13 @@ test('nonexistent file', t => {
   t.is(result.stderr, 'cat: no such file or directory: /asdfasdf');
 });
 
+test('directory', t => {
+  const result = shell.cat('resources/cat');
+  t.truthy(shell.error());
+  t.is(result.code, 1);
+  t.is(result.stderr, 'cat: resources/cat: Is a directory');
+});
+
 //
 // Valids
 //

test/head.js

@@ -18,9 +18,18 @@ test('no args', t => {
 
 test('file does not exist', t => {
   t.falsy(fs.existsSync('/asdfasdf')); // sanity check
-  const result = shell.head('/adsfasdf'); // file does not exist
+  const result = shell.head('/asdfasdf'); // file does not exist
   t.truthy(shell.error());
   t.is(result.code, 1);
+  t.is(result.stderr, 'head: no such file or directory: /asdfasdf');
+});
+
+test('directory', t => {
+  t.truthy(fs.statSync('resources/').isDirectory()); // sanity check
+  const result = shell.head('resources/');
+  t.truthy(shell.error());
+  t.is(result.code, 1);
+  t.is(result.stderr, "head: error reading 'resources/': Is a directory");
 });
 
 //

test/sort.js

@@ -25,11 +25,19 @@ test('no args', t => {
 
 test('file does not exist', t => {
   t.falsy(fs.existsSync('/asdfasdf')); // sanity check
-  const result = shell.sort('/adsfasdf');
+  const result = shell.sort('/asdfasdf');
   t.truthy(shell.error());
   t.truthy(result.code);
 });
 
+test('directory', t => {
+  t.truthy(fs.statSync('resources/').isDirectory()); // sanity check
+  const result = shell.sort('resources/');
+  t.truthy(shell.error());
+  t.is(result.code, 1);
+  t.is(result.stderr, 'sort: read failed: resources/: Is a directory');
+});
+
 //
 // Valids
 //

test/tail.js

@@ -18,11 +18,19 @@ test('no args', t => {
 
 test('file does not exist', t => {
   t.falsy(fs.existsSync('/asdfasdf')); // sanity check
-  const result = shell.tail('/adsfasdf');
+  const result = shell.tail('/asdfasdf');
   t.truthy(shell.error());
   t.is(result.code, 1);
 });
 
+test('directory', t => {
+  t.truthy(fs.statSync('resources/').isDirectory()); // sanity check
+  const result = shell.tail('resources/');
+  t.truthy(shell.error());
+  t.is(result.code, 1);
+  t.is(result.stderr, "tail: error reading 'resources/': Is a directory");
+});
+
 //
 // Valids
 //

test/uniq.js

@@ -18,11 +18,34 @@ test('no args', t => {
 
 test('file does not exist', t => {
   t.falsy(fs.existsSync('/asdfasdf')); // sanity check
-  const result = shell.sort('/adsfasdf');
+  const result = shell.uniq('/asdfasdf');
   t.truthy(shell.error());
   t.truthy(result.code);
 });
 
+test('directory', t => {
+  t.truthy(fs.statSync('resources/').isDirectory()); // sanity check
+  const result = shell.uniq('resources/');
+  t.truthy(shell.error());
+  t.is(result.code, 1);
+  t.is(result.stderr, "uniq: error reading 'resources/'");
+});
+
+test('output directory', t => {
+  t.truthy(fs.statSync('resources/').isDirectory()); // sanity check
+  const result = shell.uniq('resources/file1.txt', 'resources/');
+  t.truthy(shell.error());
+  t.is(result.code, 1);
+  t.is(result.stderr, 'uniq: resources/: Is a directory');
+});
+
+test('file does not exist with output directory', t => {
+  t.falsy(fs.existsSync('/asdfasdf')); // sanity check
+  const result = shell.uniq('/asdfasdf', 'resources/');
+  t.is(result.code, 1);
+  t.truthy(shell.error());
+});
+
 //
 // Valids
 //