Added assert, schema and remaining statement, test cases

[Vishalk91-4]

1. Does this PR affect any open issues?(Y/N) and add issue references (e.g. "fix #123", "re #123".):

• [ ] N
• [x] Y

re #8 #### 2. What is the scope of this PR (e.g. component or file name):

Added test cases for

• assert statements
• schema statements
• stmt.txt

3. Provide a description of the PR(e.g. more details, effects, motivations or doc link):

• [ ] Affects user behaviors
• [x] Contains syntax changes
• [ ] Contains variable changes
• [ ] Contains experimental features
• [ ] Performance regression: Consumes more CPU
• [ ] Performance regression: Consumes more Memory
• [ ] Other

A #### 4. Are there any breaking changes?(Y/N) and describe the breaking changes(e.g. more details, motivations or doc link): - [x] N - [ ] Y #### 5. Are there test cases for these changes?(Y/N) select and add more details, references or doc links:

• [ ] Unit test
• [ ] Integration test
• [ ] Benchmark (add benchmark stats below)
• [ ] Manual test (add detailed scripts or steps below)
• [ ] Other