Add linting for shell scripts

This changes tidy to check shell scripts for the proper shebang and
options.  It does not check that variables are formatted correctly.  It
also adds a check for the MPL 2.0 license in shell scripts.

10 files changed, 104 insertions, 13 deletions

diff --git a/components/servo/fake-ld.sh b/components/servo/fake-ld.sh
index 2babdbd80c1..f14e94ea8c9 100755
--- a/components/servo/fake-ld.sh
+++ b/components/servo/fake-ld.sh
@@ -1,3 +1,15 @@
-#!/bin/bash
-TARGET_DIR=$OUT_DIR/../../..
-arm-linux-androideabi-gcc $@ $LDFLAGS -lc -o $TARGET_DIR/libservo.so -shared && touch $TARGET_DIR/servo
+#!/usr/bin/env bash
+
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+set -o errexit
+set -o nounset
+set -o pipefail
+
+TARGET_DIR="${OUT_DIR}/../../.."
+arm-linux-androideabi-gcc "$@" \
+                          "${LDFLAGS-}" -lc -shared \
+                          -o "${TARGET_DIR}/libservo.so"
+touch "${TARGET_DIR}/servo"
diff --git a/etc/ci/check_no_unwrap.sh b/etc/ci/check_no_unwrap.sh
index f19f18d7a10..b6cf5dc837f 100755
--- a/etc/ci/check_no_unwrap.sh
+++ b/etc/ci/check_no_unwrap.sh
@@ -1,12 +1,17 @@
 #!/usr/bin/env bash
-#
+
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
 # Make sure listed files do not contain "unwrap"
 
 set -o errexit
 set -o nounset
 set -o pipefail
 
-cd "$(git rev-parse --show-toplevel)" # cd into repo root so make sure paths works in any case
+# cd into repo root to make sure paths work in any case
+cd "$(git rev-parse --show-toplevel)"
 
 # files that should not contain "unwrap"
 FILES=("components/compositing/compositor.rs"
diff --git a/etc/ci/lockfile_changed.sh b/etc/ci/lockfile_changed.sh
index e89e044f375..1d11acee473 100755
--- a/etc/ci/lockfile_changed.sh
+++ b/etc/ci/lockfile_changed.sh
@@ -1,5 +1,9 @@
 #!/usr/bin/env bash
 
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
 set -o errexit
 set -o nounset
 set -o pipefail
diff --git a/etc/ci/manifest_changed.sh b/etc/ci/manifest_changed.sh
index 31db4474099..195e4b9ef7e 100755
--- a/etc/ci/manifest_changed.sh
+++ b/etc/ci/manifest_changed.sh
@@ -1,5 +1,9 @@
 #!/usr/bin/env bash
 
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
 set -o errexit
 set -o nounset
 set -o pipefail
@@ -7,8 +11,8 @@ set -o pipefail
 # We shouldn't need any binary at all to update the manifests.
 # Adding "SKIP_TESTS" to skip tests, it doesn't really skip the tests.
 # It will run "run_wpt" with "'test_list': ['SKIP_TESTS']",
-# and then pass it into wptrunner, which won't be able to find any tests named "SKIP_TESTS",
-# and thus won't run any.
+# and then pass it into wptrunner, which won't be able to find any tests named
+# "SKIP_TESTS", and thus won't run any.
 # Adding "--binary=" to skip looking for a compiled servo binary.
 ./mach test-wpt --manifest-update --binary= SKIP_TESTS > /dev/null
 
diff --git a/etc/ci/upload_docs.sh b/etc/ci/upload_docs.sh
index c5aed30699d..fc8d7416f65 100755
--- a/etc/ci/upload_docs.sh
+++ b/etc/ci/upload_docs.sh
@@ -1,5 +1,9 @@
 #!/usr/bin/env bash
-#
+
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
 # Helper script to upload docs to doc.servo.org.
 # Requires ghp-import (from pip)
 # GitHub API token must be passed in environment var TOKEN
@@ -16,7 +20,8 @@ cp etc/doc.servo.org/* target/doc/
 
 python components/style/properties/build.py servo html
 
-OUT_DIR="`pwd`/target/doc/servo" make -f makefile.cargo -C components/script dom_docs
+OUT_DIR="$(pwd)/target/doc/servo" \
+  make -f makefile.cargo -C components/script dom_docs
 rm -rf target/doc/servo/.cache
 
 ghp-import -n target/doc
diff --git a/etc/ci/upload_nightly.sh b/etc/ci/upload_nightly.sh
index e3033cc0902..ca3d275d96d 100755
--- a/etc/ci/upload_nightly.sh
+++ b/etc/ci/upload_nightly.sh
@@ -1,5 +1,9 @@
 #!/usr/bin/env bash
 
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
 set -o errexit
 set -o nounset
 set -o pipefail
@@ -12,7 +16,7 @@ usage() {
 
 
 upload() {
-    local package_filename 
+    local package_filename
     package_filename="$(basename "${2}")"
     local -r nightly_upload_dir="s3://servo-builds/nightly/${1}"
     local -r package_upload_path="${nightly_upload_dir}/${package_filename}"
diff --git a/python/tidy/servo_tidy/licenseck.py b/python/tidy/servo_tidy/licenseck.py
index 03113da507d..dce01460d24 100644
--- a/python/tidy/servo_tidy/licenseck.py
+++ b/python/tidy/servo_tidy/licenseck.py
@@ -24,6 +24,14 @@ licenses = [
 """,
 
 """\
+#!/usr/bin/env bash
+
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+""",
+
+"""\
 #!/usr/bin/env python
 
 # This Source Code Form is subject to the terms of the Mozilla Public
diff --git a/python/tidy/servo_tidy/tidy.py b/python/tidy/servo_tidy/tidy.py
index 873af6ca22b..34eea7f882a 100644
--- a/python/tidy/servo_tidy/tidy.py
+++ b/python/tidy/servo_tidy/tidy.py
@@ -26,7 +26,7 @@ MAX_LICENSE_LINESPAN = max(len(license.splitlines()) for license in licenses)
 
 # File patterns to include in the non-WPT tidy check.
 FILE_PATTERNS_TO_CHECK = ["*.rs", "*.rc", "*.cpp", "*.c",
-                          "*.h", "Cargo.lock", "*.py",
+                          "*.h", "Cargo.lock", "*.py", "*.sh",
                           "*.toml", "*.webidl", "*.json"]
 
 # File patterns that are ignored for all tidy and lint checks.
@@ -43,6 +43,7 @@ IGNORED_FILES = [
     os.path.join(".", "tests", "wpt", "metadata", "MANIFEST.json"),
     os.path.join(".", "tests", "wpt", "metadata-css", "MANIFEST.json"),
     os.path.join(".", "components", "script", "dom", "webidls", "ForceTouchEvent.webidl"),
+    os.path.join(".", "support", "android", "openssl.sh"),
     # FIXME(pcwalton, #11679): This is a workaround for a tidy error on the quoted string
     # `"__TEXT,_info_plist"` inside an attribute.
     os.path.join(".", "components", "servo", "platform", "macos", "mod.rs"),
@@ -169,7 +170,11 @@ def check_modeline(file_name, lines):
 def check_length(file_name, idx, line):
     if file_name.endswith(".lock") or file_name.endswith(".json"):
         raise StopIteration
-    max_length = 120
+    # Prefer shorter lines when shell scripting.
+    if file_name.endswith(".sh"):
+        max_length = 80
+    else:
+        max_length = 120
     if len(line.rstrip('\n')) > max_length:
         yield (idx + 1, "Line is longer than %d characters" % max_length)
 
@@ -306,6 +311,36 @@ def check_toml(file_name, lines):
         yield (0, ".toml file should contain a valid license.")
 
 
+def check_shell(file_name, lines):
+    if not file_name.endswith(".sh"):
+        raise StopIteration
+
+    shebang = "#!/usr/bin/env bash"
+    required_options = {"set -o errexit", "set -o nounset", "set -o pipefail"}
+
+    if len(lines) == 0:
+        yield (0, 'script is an empty file')
+    else:
+        if lines[0].rstrip() != shebang:
+            yield (1, 'script does not have shebang "{}"'.format(shebang))
+
+        for idx in range(1, len(lines)):
+            stripped = lines[idx].rstrip()
+
+            # Comments or blank lines are ignored. (Trailing whitespace is caught with a separate linter.)
+            if lines[idx].startswith("#") or stripped == "":
+                continue
+            elif stripped in required_options:
+                required_options.remove(stripped)
+            else:
+                # The first non-comment, non-whitespace, non-option line is the first "real" line of the script.
+                # The shebang, options, etc. must come before this.
+                if len(required_options) != 0:
+                    formatted = ['"{}"'.format(opt) for opt in required_options]
+                    yield (idx + 1, "script is missing options {}".format(", ".join(formatted)))
+                    break
+
+
 def check_rust(file_name, lines):
     if not file_name.endswith(".rs") or \
        file_name.endswith(".mako.rs") or \
@@ -694,7 +729,8 @@ def scan(only_changed_files=False, progress=True):
     # standard checks
     files_to_check = filter_files('.', only_changed_files, progress)
     checking_functions = (check_flake8, check_lock, check_webidl_spec, check_json)
-    line_checking_functions = (check_license, check_by_line, check_toml, check_rust, check_spec, check_modeline)
+    line_checking_functions = (check_license, check_by_line, check_toml, check_shell,
+                               check_rust, check_spec, check_modeline)
     errors = collect_errors_for_files(files_to_check, checking_functions, line_checking_functions)
     # check dependecy licenses
     dep_license_errors = check_dep_license_errors(get_dep_toml_files(only_changed_files), progress)
diff --git a/python/tidy/servo_tidy_tests/shell_tidy.sh b/python/tidy/servo_tidy_tests/shell_tidy.sh
new file mode 100644
index 00000000000..fbf0e784755
--- /dev/null
+++ b/python/tidy/servo_tidy_tests/shell_tidy.sh
@@ -0,0 +1,7 @@
+#!/bin/bash
+#
+# Tests tidy for shell scripts.
+
+set -o nounset
+
+echo "hello world"
diff --git a/python/tidy/servo_tidy_tests/test_tidy.py b/python/tidy/servo_tidy_tests/test_tidy.py
index 8db19a5efd7..3ad7e03d667 100644
--- a/python/tidy/servo_tidy_tests/test_tidy.py
+++ b/python/tidy/servo_tidy_tests/test_tidy.py
@@ -48,6 +48,12 @@ class CheckTidiness(unittest.TestCase):
         self.assertEqual('incorrect license', errors.next()[2])
         self.assertNoMoreErrors(errors)
 
+    def test_shell(self):
+        errors = tidy.collect_errors_for_files(iterFile('shell_tidy.sh'), [], [tidy.check_shell], print_text=False)
+        self.assertEqual('script does not have shebang "#!/usr/bin/env bash"', errors.next()[2])
+        self.assertEqual('script is missing options "set -o errexit", "set -o pipefail"', errors.next()[2])
+        self.assertNoMoreErrors(errors)
+
     def test_rust(self):
         errors = tidy.collect_errors_for_files(iterFile('rust_tidy.rs'), [], [tidy.check_rust], print_text=False)
         self.assertEqual('use statement spans multiple lines', errors.next()[2])