Add support for multiple contracts

[eswarasai]

Description

Figure out how solc-js and sabre handle different cases like below:

• Multiple separate contracts in a single file
• Base contract and inherited contract in the same file
• Base contract in an imported file

[gitcoinbot]

Issue Status: 1. Open 2. Started 3. Submitted 4. Done

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This issue now has a funding of 1.2 ETH (161.85 USD @ $134.88/ETH) attached to it as part of the MythX fund.

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[gitcoinbot]

Issue Status: 1. Open 2. Started 3. Submitted 4. Done

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Work has been started.

These users each claimed they can complete the work by 12 months from now.
Please review their action plans below:

1) eswarasai has been approved to start work.

Will look into a way to support compilation of the above listed cases

Learn more on the Gitcoin Issue Details page.

[eswarasai]

@b-mueller -- Here are my findings for the current setup of solc and sabre for different scenarios:

1. Multiple separate contracts in a single file
   solc returns all the contracts as object with keys sorted in alphabetical order of the contract name. sabre picks up the first contract from the object and generates MythX report for that

2. Base contract and inherited contract in the same file
   This works same as the above

3. Base contract in an imported file
   This might be quite not possible yet as solc itself doesn't support importing files within contract -- Support imports in solcjs CLI ethereum/solc-js#114

Let me know how you'd like me to proceed further :)

[muellerberndt]

solc itself doesn't support importing files within contract

Ok, that sucks. Then there's also no easy way to fix #9.

I think in most cases it makes sense to return the analysis result for the contract with the longest byte code, which (if I'm not mistaken) should be the lowest in the inheritance hierarchy. Should we try that first?

[gitcoinbot]

Issue Status: 1. Open 2. Started 3. Submitted 4. Done

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Work for 1.2 ETH (164.15 USD @ $136.79/ETH) has been submitted by:

1. @eswarasai

@b-mueller please take a look at the submitted work:

• PR by @eswarasai

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• Learn more on the Gitcoin Issue Details page
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• Questions? Checkout Gitcoin Help or the Gitcoin Slack
• $42,362.59 more funded OSS Work available on the Gitcoin Issue Explorer

[gitcoinbot]

Issue Status: 1. Open 2. Started 3. Submitted 4. Done

---

The funding of 1.2 ETH (164.15 USD @ $136.79/ETH) attached to this issue has been approved & issued to @eswarasai.

• Learn more on the Gitcoin Issue Details page
• Questions? Checkout Gitcoin Help or the Gitcoin Slack
• $42,034.29 more funded OSS Work available on the Gitcoin Issue Explorer