Reviewing files that changed from the base of the PR and between 25d9279 and 3eedf0b.

• internal/parser/__snapshots__/parser_fault_tolerance_test.snap is excluded by !**/*.snap, !**/*.snap
• internal/parser/__snapshots__/parser_test.snap is excluded by !**/*.snap, !**/*.snap

• Lexer.g4 (1 hunks)
• Numscript.g4 (1 hunks)
• internal/analysis/check.go (2 hunks)
• internal/analysis/check_test.go (1 hunks)
• internal/flags/flags.go (2 hunks)
• internal/interpreter/balances.go (1 hunks)
• internal/interpreter/batch_balances_query.go (4 hunks)
• internal/interpreter/evaluate_expr.go (1 hunks)
• internal/interpreter/interpreter.go (9 hunks)
• internal/interpreter/interpreter_test.go (1 hunks)
• internal/interpreter/reconciler.go (3 hunks)
• internal/interpreter/reconciler_test.go (9 hunks)
• internal/parser/antlrParser/Lexer.interp (4 hunks)
• internal/parser/antlrParser/Lexer.tokens (2 hunks)
• internal/parser/antlrParser/Numscript.interp (4 hunks)
• internal/parser/antlrParser/Numscript.tokens (2 hunks)
• internal/parser/antlrParser/lexer.go (2 hunks)
• internal/parser/antlrParser/numscript_base_listener.go (1 hunks)
• internal/parser/antlrParser/numscript_listener.go (2 hunks)
• internal/parser/antlrParser/numscript_parser.go (67 hunks)
• internal/parser/ast.go (2 hunks)
• internal/parser/parser.go (4 hunks)
• internal/parser/parser_test.go (1 hunks)

Lexer.g4 (1)

34-34: Good addition of the RESTRICT token for asset coloring

The backslash character ('\\') has been added as a new lexer token to implement the "restriction" operator mentioned in the PR objectives. This token will be used to introduce color constraints in source specifications.

internal/flags/flags.go (1)

12-12: Feature flag properly added for experimental asset colors

Good practice to gate this new functionality behind a feature flag, allowing for controlled rollout and maintaining backward compatibility. The flag is appropriately added to both the constants section and the AllFlags slice.

Also applies to: 22-22

internal/parser/ast.go (3)

136-137: AST updated to support color constraints on source accounts

The addition of the Color field to the SourceAccount struct enables representing color constraints in the AST. This is a crucial part of the implementation for the asset coloring feature.

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169-170: AST updated to support color constraints on overdrafts

The addition of the Color field to the SourceOverdraft struct enables representing color constraints for overdrafts, which aligns with the PR objective of allowing different maximum amounts and overdraft permissions for colored sub-assets.

---

136-137:

✅ Verification successful

Verify type compatibility with existing Color struct

I notice there's a Color struct in the codebase (internal/lsp/lsp_types/bindings.go) with different fields. While they're in different packages, it's worth verifying this won't cause any confusion.

Also applies to: 169-170

---

🏁 Script executed:

#!/bin/bash
# Check for any imports of lsp_types in files that might now use the new Color field
rg "import.*internal/lsp/lsp_types" -A 10
# Check for any methods or functions that might be working with both types of Color
rg "func.*Color" --type go

Length of output: 3936

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No conflicts between parser’s Color and lsp_types.Color

The new Color ValueExpr field in internal/parser/ast.go lives entirely within the parser package and never imports or references internal/lsp/lsp_types.Color. No compatibility issues detected—no further action needed.

internal/parser/antlrParser/numscript_listener.go (2)

76-77: Implementation follows interface pattern correctly.

The addition of EnterColorConstraint listener method correctly matches the pattern established throughout the interface for handling grammar productions.

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208-209: Implementation follows interface pattern correctly.

The addition of ExitColorConstraint listener method correctly matches the pattern established throughout the interface for handling grammar productions.

internal/parser/antlrParser/numscript_base_listener.go (1)

155-157:

✅ Verification successful

Implementation follows base listener pattern correctly.

The empty implementation of EnterColorConstraint matches the pattern used throughout the base listener class.

Static analysis indicates this line isn't covered by tests. Consider adding tests for color constraint parsing.

---

🏁 Script executed:

#!/bin/bash
# Check for test coverage of color constraint parsing
cd internal/parser
grep -r "TestParse.*Color" --include="*.go" .

Length of output: 68

---

🏁 Script executed:

#!/bin/bash
# Search for any tests covering ColorConstraint parsing under internal/parser
grep -Rni "ColorConstraint" --include="*_test.go" internal/parser
grep -Rni "colorConstraint" --include="*_test.go" internal/parser
grep -Rni "color" --include="*_test.go" internal/parser

Length of output: 452

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#!/bin/bash
# Display context around TestColorRestriction tests
sed -n '470,530p' internal/parser/parser_test.go

---

Approve EnterColorConstraint and existing test coverage

The empty EnterColorConstraint implementation correctly follows the base listener pattern, and the parser already includes tests for color constraints:

• TestColorRestriction, TestColorRestrictionBoundedOverdraft, and TestColorRestrictionUnboundedOverdraft in internal/parser/parser_test.go cover color constraint parsing.

No additional tests are required.

🧰 Tools

🪛 GitHub Check: codecov/patch

[warning] 156-156: internal/parser/antlrParser/numscript_base_listener.go#L156
Added line #L156 was not covered by tests

internal/interpreter/evaluate_expr.go (1)

104-109: Well-designed helper function for optional expression evaluation.

This new generic helper function elegantly handles nil expressions by returning nil without error, otherwise delegating to the existing evaluateExprAs function. This simplifies code in callers that need to evaluate optional color constraints.

internal/analysis/check.go (3)

479-479: Properly validates color expression type.

The color constraint is correctly validated as a string type, which is appropriate for this feature.

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487-495: Color-aware account tracking.

The implementation creates a unique identifier for colored accounts by appending a representation of the color constraint to the account name. This approach correctly distinguishes between the same account with different color constraints.

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521-521: Properly validates color expression for overdraft sources.

The color constraint is correctly validated as a string type for overdraft sources as well.

internal/parser/parser.go (2)

163-171: Helper is concise & nil‑safe – looks good

The parseColorConstraint helper cleanly encapsulates the optional parse logic and already copes with a missing node (nil).
No functional or stylistic issues spotted here.

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180-186: Color now parsed for SourceAccount – check downstream handling

The new Color field is correctly filled, but make sure every downstream consumer (analysis, interpreter, reconciler, etc.) gracefully handles a nil value. A quick grep shows at least the interpreter uses evaluateOptExprAs, which is 👍. Just double‑check tests for weird inputs like \ "".

internal/parser/antlrParser/Numscript.tokens (2)

32-42: Token addition correctly implements the asset coloring feature

The introduction of the RESTRICT token at position 32 with the backslash character appropriately supports the new asset coloring feature. The shifting of subsequent token values maintains the lexer's integrity.

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70-72: Character token assignments properly updated

The character token assignments have been properly updated to include the new backslash character and adjust the position of subsequent tokens.

internal/interpreter/reconciler.go (3)

25-29: Sender struct extension looks good

The addition of the Color *string field to the Sender struct is appropriate for carrying color information throughout the reconciliation process.

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87-91: Color preservation in leftover sender entries

Good implementation of preserving the color attribute when appending a leftover sender entry back to the senders stack. This ensures color information isn't lost during reconciliation.

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103-109: Asset coloring in posting creation and merging

The implementation correctly integrates color information into the asset string for postings and updates the merging logic to consider colored assets as distinct entities.

internal/parser/parser_test.go (3)

478-485: Basic color restriction test looks good

This test appropriately verifies the parsing of a simple color restriction with a literal string value.

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487-494: Color restriction with bounded overdraft test

Good test coverage for the combined use of color restrictions with bounded overdraft functionality.

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496-503: Variable color and unbounded overdraft test

Excellent coverage of the variable color expression with unbounded overdraft, ensuring the parser correctly handles these complex combinations.

internal/parser/antlrParser/Lexer.tokens (2)

32-42: Token addition for RESTRICT correctly implemented

The Lexer tokens have been properly updated to include the new RESTRICT token for the backslash character, with appropriate adjustments to token numbering.

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70-72: Character-to-token mappings properly updated

The character-to-token mappings have been correctly updated to include the backslash character and adjust subsequent mappings.

Numscript.g4 (2)

44-44: The new colorConstraint rule enhances expressiveness

This new parser rule introduces asset coloring functionality, enabling the restriction operator (\) to specify a sub-asset from which to pull assets.

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46-50: Well-structured source rule modifications

The changes to the source rule properly integrate the optional colorConstraint into the three appropriate alternatives. This implementation is clean and maintains backward compatibility by making the color constraint optional.

internal/parser/antlrParser/lexer.go (2)

49-50: Correct addition of the RESTRICT token literal

The backslash character has been properly added to the LiteralNames slice to represent the RESTRICT token.

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304-314: Token indices properly updated

All token constants following the new LexerRESTRICT = 32 have been correctly incremented by one to maintain proper token indexing.

internal/analysis/check_test.go (3)

865-890: Comprehensive test for color variables

This test properly verifies that unbound string-typed variables used as colors produce appropriate diagnostics with the correct variable names and types. The test covers both regular account sources and those with unbounded overdraft.

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892-907: Good test for colored account differentiation

This test confirms an important aspect of the feature: accounts with different colors are treated as distinct assets, even when they share the same base account. This allows for proper tracking of sub-assets.

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909-929: Important edge case for empty color strings

This test validates the correct handling of empty color strings, ensuring they are treated as equivalent to no color and generate appropriate warnings for redundant accounts. The expectation of an EmptiedAccount diagnostic is appropriate for this case.

internal/interpreter/reconciler_test.go (5)

39-39: Updated Sender initializations

All existing Sender struct initializations have been properly updated to include the new Color field set to nil, maintaining compatibility with the updated struct definition.

Also applies to: 48-48, 62-62, 70-70, 91-92, 106-107, 125-126, 144-146, 160-160

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171-180: Good basic test for colored asset reconciliation

This test verifies the fundamental behavior of colored asset reconciliation, ensuring that a colored asset in the source results in a posting with the proper colored asset string format (COIN*x).

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182-197: Complete testing of multiple destinations with colored assets

This test correctly verifies that a colored source can distribute to multiple destinations while maintaining the color information in all resulting postings.

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199-214: Important test for multiple colored sources

This test verifies a critical functionality: when multiple sources with different colors send to the same destination, the resulting postings correctly preserve each color's identity rather than merging them.

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216-218: Useful generic helper function

The pointer generic function is a clean utility that simplifies creating pointers to string literals for the color field. This approach is more concise than repeatedly using address-of operators with variables.

internal/interpreter/interpreter.go (6)

304-309: Modified signature now includes color parameter

The pushSender method has been updated to include a color *string parameter and store it in the Sender struct, which supports the new asset coloring feature.

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494-495: Correctly passes color parameter from source account

The sendAll function now correctly passes the Color field from the SourceAccount to sendAllToAccount.

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505-506: Correctly passes color parameter from source overdraft

The sendAll function now correctly passes the Color field from the SourceOverdraft to sendAllToAccount.

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607-608: Correctly passes color parameter from source account

The color field is now properly passed to trySendingToAccount from SourceAccount.

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618-619: Correctly passes color parameter from source overdraft

The color field is now properly passed to trySendingToAccount from SourceOverdraft.

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878-879: Updated to support colored assets in balance queries

The getBalance function call to batchQuery now includes a nil third parameter to match the updated signature that supports colored assets.

internal/interpreter/interpreter_test.go (5)

4198-4220: Good basic test for color sending functionality

This test verifies that using the \ operator with a color string on a source account results in a posting with the asset formatted as ASSET*color. The test is well-structured and comprehensive.

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4246-4271: Well-designed test for balance restrictions with colors

This test correctly verifies that the interpreter uses the balance of the colored asset when fetching from a source with a color restriction, even when the uncolored balance is insufficient.

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4297-4319: Comprehensive test for colored assets with send all operation

This test correctly verifies that the send all operation works with colored assets, checking both the source restriction and the resulting posting.

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4321-4363: Thorough test for multiple colored sources

This test effectively verifies the correct behavior when multiple color restrictions are used in order, including both colored and uncolored assets from the same account.

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4365-4390: Important edge case test for empty color strings

This test handles the important edge case of empty string colors, verifying that they behave the same as uncolored assets. This is a good defensive programming practice.

internal/parser/antlrParser/numscript_parser.go (1)

38-48:

✅ Verification successful

Token index shift – please confirm all downstream usages were regenerated

RESTRICT is appended at index 32 inside both LiteralNames and SymbolicNames.
Because these constant values are referenced everywhere (manual traversals, unit tests, interpreter switch‑statements, etc.), any place that was not regenerated from the grammar will now be off‑by‑one starting at the new token.

Please double‑check that:

1. Lexer.g4 / Numscript.g4 were updated (not just the generated Go file).
2. All consumers were re‑generated (go generate, antlr, etc.) instead of hand‑edited – otherwise the shift silently corrupts parsing.
3. Custom assertions in tests (e.g., hard‑coded numeric token values) were adapted.

Would you run a quick search to make sure no magic numbers >=32 are still hard‑coded?

---

🏁 Script executed:

#!/bin/bash
# Look for suspicious numeric token literals >= 32 used outside generated files
fd -t f -e go | grep -v "internal/parser/antlrParser" | xargs rg --line-number '\b3[2-9]\b|\b[4-9][0-9]\b'

Length of output: 10955

---

No hard‑coded token indices detected outside the generated parser

I ran the specified search for numeric literals ≥ 32 and found only domain‑specific values (version numbers, line/character positions, monetary/test data, etc.)—no instances of manual token index references. All parser tokens appear to be consumed via the regenerated constants.

Reviewing files that changed from the base of the PR and between 4a1b263 and a860185.

• internal/interpreter/evaluate_expr.go (2 hunks)
• internal/interpreter/interpreter.go (9 hunks)
• internal/interpreter/interpreter_error.go (1 hunks)
• internal/interpreter/interpreter_test.go (1 hunks)

• internal/interpreter/evaluate_expr.go
• internal/interpreter/interpreter_test.go
• internal/interpreter/interpreter.go