examples/sites/syntaxviewer: initial commit

Syntax viewer is an incredibly simple application for viewing the syntax
tree representations of different languages.

As part of this we vendor mvdan.cc/sh/syntax and its deps.

We also re-enable AriaSet for now until we get
gopherjs/gopherjs#779 merged.

We also add the float CSS attribute.

And fix some of the JSX parsing.

Author: myitcv

.vendor.txt

@@ -24,3 +24,4 @@
     ./_vendor/src/honnef.co/go/js/xhr                        00e3346113aed89b501ead4e863c7c3d04fa0c5b  git@github.com:dominikh/go-js-xhr
     ./_vendor/src/honnef.co/go/js/util                       96b8dd9d16214b6cd9d8c8e84b3a375da4688108  git@github.com:dominikh/go-js-util
     ./_vendor/src/honnef.co/go/js/dom                        0a64a2db1425c1881d4ec762370250c65f44b85b  git@github.com:dominikh/go-js-dom
+    ./_vendor/src/mvdan.cc/sh                                0e64bc087f8341d164c07a5edba1e37417bd2df4  git@github.com:mvdan/sh

_vendor/src/mvdan.cc/sh/.travis.yml

@@ -0,0 +1,22 @@
+language: go
+
+matrix:
+  include:
+    - os: linux
+      dist: trusty
+      sudo: false
+      go: 1.9.x
+    - os: linux
+      dist: trusty
+      sudo: false
+      go: 1.10.x
+    - os: osx
+      osx_image: xcode9.2
+      go: 1.10.x
+
+go_import_path: mvdan.cc/sh
+
+script:
+  - go test ./...
+  - go test -short -race ./...
+  - shfmt -version

_vendor/src/mvdan.cc/sh/LICENSE

@@ -0,0 +1,27 @@
+Copyright (c) 2016, Daniel Martí. All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+   * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+   * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+   * Neither the name of the copyright holder nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

_vendor/src/mvdan.cc/sh/README.md

@@ -0,0 +1,114 @@
+# sh
+
+[![GoDoc](https://godoc.org/mvdan.cc/sh?status.svg)](https://godoc.org/mvdan.cc/sh)
+[![Linux & OSX build](https://travis-ci.org/mvdan/sh.svg?branch=master)](https://travis-ci.org/mvdan/sh)
+[![Windows build](https://ci.appveyor.com/api/projects/status/rxxs08v65aj2fqof?svg=true)](https://ci.appveyor.com/project/mvdan/sh)
+[![Coverage Status](https://coveralls.io/repos/github/mvdan/sh/badge.svg?branch=master)](https://coveralls.io/github/mvdan/sh)
+
+A shell parser, formatter and interpreter. Supports [POSIX Shell],
+[Bash] and [mksh]. Requires Go 1.9 or later.
+
+### shfmt
+
+	go get -u mvdan.cc/sh/cmd/shfmt
+
+`shfmt` formats shell programs. It can use tabs or any number of spaces
+to indent. See [canonical.sh](syntax/canonical.sh) for a quick look at
+its default style.
+
+You can feed it standard input, any number of files or any number of
+directories to recurse into. When recursing, it will operate on `.sh`
+and `.bash` files and ignore files starting with a period. It will also
+operate on files with no extension and a shell shebang.
+
+	shfmt -l -w script.sh
+
+Use `-i N` to indent with a number of spaces instead of tabs. There are
+other formatting options - see `shfmt -h`. For example, to get the
+formatting appropriate for [Google's Style][google-style] guide, use
+`shfmt -i 2 -ci`.
+
+Packages are available for [Arch], [CRUX], [Homebrew], [NixOS] and [Void].
+
+#### Advantages over `bash -n`
+
+`bash -n` can be useful to check for syntax errors in shell scripts.
+However, `shfmt >/dev/null` can do a better job as it checks for invalid
+UTF-8 and does all parsing statically, including checking POSIX Shell
+validity:
+
+```
+ $ echo '${foo:1 2}' | bash -n
+ $ echo '${foo:1 2}' | shfmt
+1:9: not a valid arithmetic operator: 2
+ $ echo 'foo=(1 2)' | bash --posix -n
+ $ echo 'foo=(1 2)' | shfmt -p
+1:5: arrays are a bash feature
+```
+
+### gosh
+
+	go get -u mvdan.cc/sh/cmd/gosh
+
+Experimental shell that uses `interp`. Work in progress, so don't expect
+stability just yet.
+
+### Fuzzing
+
+This project makes use of [go-fuzz] to find crashes and hangs in both
+the parser and the printer. To get started, run:
+
+	git checkout fuzz
+	./fuzz
+
+### Caveats
+
+* Bash index expressions must be an arithmetic expression or a quoted
+  string. This is because the static parser can't know whether the array
+  is an associative array (string keys) since that depends on having
+  called or not `declare -A`.
+
+```
+ $ echo '${array[spaced string]}' | shfmt
+1:16: not a valid arithmetic operator: string
+```
+
+* `$((` and `((` ambiguity is not suported. Backtracking would greatly
+  complicate the parser and make stream support - `io.Reader` -
+  impossible. In practice, the POSIX spec recommends to [space the
+  operands][posix-ambiguity] if `$( (` is meant.
+
+```
+ $ echo '$((foo); (bar))' | shfmt
+1:1: reached ) without matching $(( with ))
+```
+
+* Some builtins like `export` and `let` are parsed as keywords. This is
+  to allow statically parsing them and building their AST, as opposed to
+  just keeping the arguments as a slice of arguments.
+
+### Related projects
+
+* [dockerised-shfmt] - A docker image of `shfmt`
+* [format-shell] - Atom plugin for `shfmt`
+* [micro] - Editor with a built-in plugin for `shfmt`
+* [shell-format] - VS Code plugin for `shfmt`
+* [vim-shfmt] - Vim plugin for `shfmt`
+
+[arch]: https://aur.archlinux.org/packages/shfmt/
+[bash]: https://www.gnu.org/software/bash/
+[crux]: https://github.com/6c37/crux-ports-git/tree/3.3/shfmt
+[dockerised-shfmt]: https://hub.docker.com/r/jamesmstone/shfmt/
+[examples]: https://godoc.org/mvdan.cc/sh/syntax#pkg-examples
+[format-shell]: https://atom.io/packages/format-shell
+[go-fuzz]: https://github.com/dvyukov/go-fuzz
+[google-style]: https://google.github.io/styleguide/shell.xml
+[homebrew]: https://github.com/Homebrew/homebrew-core/blob/HEAD/Formula/shfmt.rb
+[micro]: https://micro-editor.github.io/
+[mksh]: https://www.mirbsd.org/mksh.htm
+[nixos]: https://github.com/NixOS/nixpkgs/blob/HEAD/pkgs/tools/text/shfmt/default.nix
+[posix shell]: http://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html
+[posix-ambiguity]: http://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#tag_18_06_03
+[shell-format]: https://marketplace.visualstudio.com/items?itemName=foxundermoon.shell-format
+[vim-shfmt]: https://github.com/z0mbix/vim-shfmt
+[void]: https://github.com/voidlinux/void-packages/blob/HEAD/srcpkgs/shfmt/template

_vendor/src/mvdan.cc/sh/appveyor.yml

@@ -0,0 +1,21 @@
+version: "{build}"
+
+clone_folder: c:\gopath\src\mvdan.cc\sh
+
+environment:
+  GOPATH: c:\gopath
+  GOVERSION: 1.10
+
+install:
+  - rmdir c:\go /s /q
+  - appveyor DownloadFile https://storage.googleapis.com/golang/go%GOVERSION%.windows-amd64.msi
+  - msiexec /i go%GOVERSION%.windows-amd64.msi /q
+  - go version
+
+build: false
+deploy: false
+
+test_script:
+  - go get -d -t ./...
+  - go install -v ./...
+  - go test ./...

_vendor/src/mvdan.cc/sh/cmd/gosh/main.go

@@ -0,0 +1,107 @@
+// Copyright (c) 2017, Daniel Martí <mvdan@mvdan.cc>
+// See LICENSE for licensing information
+
+package main // import "mvdan.cc/sh/cmd/gosh"
+
+import (
+	"flag"
+	"fmt"
+	"io"
+	"os"
+	"strings"
+
+	"golang.org/x/crypto/ssh/terminal"
+
+	"mvdan.cc/sh/interp"
+	"mvdan.cc/sh/syntax"
+)
+
+var (
+	command = flag.String("c", "", "command to be executed")
+
+	parser *syntax.Parser
+
+	runner = interp.Runner{
+		Stdin:  os.Stdin,
+		Stdout: os.Stdout,
+		Stderr: os.Stderr,
+	}
+)
+
+func main() {
+	flag.Parse()
+	if err := runAll(); err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(1)
+	}
+}
+
+func runAll() error {
+	parser = syntax.NewParser()
+	if *command != "" {
+		return run(strings.NewReader(*command), "")
+	}
+	if flag.NArg() == 0 {
+		if terminal.IsTerminal(int(os.Stdin.Fd())) {
+			return interactive()
+		}
+		return run(os.Stdin, "")
+	}
+	for _, path := range flag.Args() {
+		if err := runPath(path); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func runPath(path string) error {
+	f, err := os.Open(path)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+	return run(f, path)
+}
+
+func run(reader io.Reader, name string) error {
+	prog, err := parser.Parse(reader, name)
+	if err != nil {
+		return err
+	}
+	runner.Reset()
+	return runner.Run(prog)
+}
+
+type promptReader struct {
+	io.Reader
+	first bool
+}
+
+func (pr *promptReader) Read(p []byte) (int, error) {
+	if pr.first {
+		fmt.Printf("$ ")
+		pr.first = false
+	} else {
+		fmt.Printf("> ")
+	}
+	return pr.Reader.Read(p)
+}
+
+func interactive() error {
+	r := &promptReader{os.Stdin, true}
+	runner.Reset()
+	fn := func(s *syntax.Stmt) bool {
+		if err := runner.Stmt(s); err != nil {
+			code, ok := err.(interp.ExitCode)
+			if ok {
+				os.Exit(int(code))
+			}
+			fmt.Fprintln(os.Stderr, err)
+			os.Exit(1)
+		}
+		r.first = true
+		return true
+	}
+	return parser.Stmts(r, fn)
+}