embark run crashes if a contract is deleted

[bingen]

Bug Report

Dashboard crash when deleting contracts

Current behavior

If you have embark run dashboard active and then delete a .sol file inside the contracts/ path, it crashes.

It happens often to me because I have an emacs package that is constantly creating and deleting temporary files for syntax checking, but I happened to me once I was deleting a contract that I was no longer using.

@iurimatias suggested a workaround consisting of adding a negative match pattern in embark.json, like this:

"contracts": ["contracts/**", "!contracts/**/flycheck_*.sol"],

This works for me for the first case.

Expected behavior

Not sure, but it should definitely not crash, specially if the file is not actually needed

If you encounter an error, please create a logfile using the following command and post the output here

Error: ENOENT: no such file or directory, open 'contracts/test/mocks/flycheck_TokenMock.sol'
    at Object.fs.openSync (fs.js:663:18)
    at Function.fs.readFileSync (fs.js:568:33)
    at restrictPath (/home/bingen/.nvm/versions/node/v9.4.0/lib/node_modules/embark/lib/core/fs.js:54:43)
    at Object.readFileSync (/home/bingen/.nvm/versions/node/v9.4.0/lib/node_modules/embark/lib/core/fs.js:111:10)
    at File.content (/home/bingen/.nvm/versions/node/v9.4.0/lib/node_modules/embark/lib/core/file.js:137:20)
    at /home/bingen/.nvm/versions/node/v9.4.0/lib/node_modules/embark/lib/modules/solidity/index.js:172:18
    at /home/bingen/.nvm/versions/node/v9.4.0/lib/node_modules/embark/node_modules/async/dist/async.js:3110:16
    at eachOfArrayLike (/home/bingen/.nvm/versions/node/v9.4.0/lib/node_modules/embark/node_modules/async/dist/async.js:1069:9)
    at eachOf (/home/bingen/.nvm/versions/node/v9.4.0/lib/node_modules/embark/node_modules/async/dist/async.js:1117:5)
    at Object.eachLimit (/home/bingen/.nvm/versions/node/v9.4.0/lib/node_modules/embark/node_modules/async/dist/async.js:3172:5)
    at prepareInput (/home/bingen/.nvm/versions/node/v9.4.0/lib/node_modules/embark/lib/modules/solidity/index.js:161:15)
    at nextTask (/home/bingen/.nvm/versions/node/v9.4.0/lib/node_modules/embark/node_modules/async/dist/async.js:5324:14)
    at Object.waterfall (/home/bingen/.nvm/versions/node/v9.4.0/lib/node_modules/embark/node_modules/async/dist/async.js:5334:5)
    at Solidity.compile_solidity (/home/bingen/.nvm/versions/node/v9.4.0/lib/node_modules/embark/lib/modules/solidity/index.js:159:11)
    at /home/bingen/.nvm/versions/node/v9.4.0/lib/node_modules/embark/lib/modules/compiler/index.js:50:18
    at /home/bingen/.nvm/versions/node/v9.4.0/lib/node_modules/embark/lib/utils/async_extend.js:7:7
    at /home/bingen/.nvm/versions/node/v9.4.0/lib/node_modules/embark/node_modules/async/dist/async.js:3110:16
    at eachOfArrayLike (/home/bingen/.nvm/versions/node/v9.4.0/lib/node_modules/embark/node_modules/async/dist/async.js:1069:9)
    at eachOf (/home/bingen/.nvm/versions/node/v9.4.0/lib/node_modules/embark/node_modules/async/dist/async.js:1117:5)
    at Object.eachLimit (/home/bingen/.nvm/versions/node/v9.4.0/lib/node_modules/embark/node_modules/async/dist/async.js:3172:5)
    at Object.asyncEachObject [as eachObject] (/home/bingen/.nvm/versions/node/v9.4.0/lib/node_modules/embark/lib/utils/async_extend.js:4:9)
    at Compiler.compile_contracts (/home/bingen/.nvm/versions/node/v9.4.0/lib/node_modules/embark/lib/modules/compiler/index.js:36:11)

Please provide additional information about your system

OS: Ubuntu 16.04
Embark Version: 4.0.0-alpha.1
Node Version: v.9.4.0
NPM Version: 5.7.1

[0x-r4bbit]

This will be fixed with: #1104