Add visualization of ASTs to CLI & REPL

[jpschorr]

Add visualization of ASTs to CLI & REPL

• Make modules for existing functionality of error and repl
• Add actual arg parsing to CLI
• Make REPL a sub-mode initiated by a CLI command
• Add partial (lots of todo!()s) translation of AST into graphviz
• Add FFI to graphviz to layout & render
• Add display mode which prints image to console

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NOTE: You will need to brew install graphviz or system-equivalent prior to the following.

For example, running:

cargo run --release --features visualize -- ast -Tpng "SELECT num.*, num BETWEEN 2 AND 15 FROM (SELECT tbl.a[8] + ((4/-2)+(7*sin(7))-2.0) - xform(1,position('x' in 'yxz')), NULL FROM tbl WHERE tbl.b LIKE 'foo%') as num" > /tmp/ast.png

shows

Or, run

cargo run --release --features visualize -- ast -Tdisplay "SELECT num.*, num BETWEEN 2 AND 15 FROM (SELECT tbl.a[8] + ((4/-2)+(7*sin(7))-2.0) - xform(1,position('x' in 'yxz')), NULL FROM tbl WHERE tbl.b LIKE 'foo%') as num"

to display the image directly in the terminal (for any terminal supported by viuer)

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By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[codecov]

Codecov Report

Merging #158 (7cef2ba) into main (62a2159) will increase coverage by 0.50%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main     partiql/partiql-lang-rust#158      +/-   ##
==========================================
+ Coverage   84.03%   84.54%   +0.50%     
==========================================
  Files          20       20              
  Lines        2362     2348      -14     
==========================================
  Hits         1985     1985              
+ Misses        377      363      -14     

Impacted Files	Coverage Δ
partiql-parser/src/error.rs	84.21% <0.00%> (+16.60%)	⬆️

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[github-actions]

Conformance comparison report

	main (62a2159)	a4b16e0	+/-
% Passing	75.85%	75.85%	0.00%
✅ Passing	333	333	0
❌ Failing	47	47	0
🔶 Ignored	59	59	0
Total Tests	439	439	0

Number passing in both: 333

Number failing in both: 47

Number passing in main but now fail: 0

Number failing in main but now pass: 0

[alancai98]

Very cool work here. The visualization makes the AST (and future IR) much more comprehensible and easier to view the parser's output. Left mostly minor comments and a possible parser bug (related to path expressions).