feat: resolve built in constants in graph without environment

src/dataflow/eval/resolve/alias-tracking.ts

@@ -14,7 +14,7 @@ import { DfEdge, EdgeType } from '../../graph/edge';
 import type { DataflowGraph } from '../../graph/graph';
 import { onReplacementOperator, type ReplacementOperatorHandlerArgs } from '../../graph/unknown-replacement';
 import { onUnknownSideEffect } from '../../graph/unknown-side-effect';
-import { VertexType } from '../../graph/vertex';
+import { isValueVertex, VertexType } from '../../graph/vertex';
 import { valueFromRNodeConstant, valueFromTsValue } from '../values/general';
 import { Bottom, isTop, type Lift, Top, type Value, type ValueSet } from '../values/r-value';
 import { setFrom } from '../values/sets/set-constants';
@@ -380,6 +380,11 @@ export function trackAliasesInGraph(id: NodeId, graph: DataflowGraph, ctx: ReadO
 
 	const values: Set<Value> = new Set<Value>();
 	for(const id of resultIds) {
+		const vertex = graph.getVertex(id);
+		if(isValueVertex(vertex) && vertex.value !== undefined) {
+			values.add(vertex.value);
+			continue;
+		}
 		const node = idMap.get(id);
 		if(node !== undefined) {
 			if(node.info.role === RoleInParent.ParameterDefaultValue || RNode.iterateParents(node, idMap).some(p => p.info.role === RoleInParent.ParameterDefaultValue)) {

src/dataflow/graph/vertex.ts

@@ -5,6 +5,7 @@ import type { REnvironmentInformation } from '../environments/environment';
 import type { ControlDependency, ExitPoint } from '../info';
 import type { Identifier } from '../environments/identifier';
 import type { BuiltInProcName } from '../environments/built-in-proc-name';
+import type { Value } from '../eval/values/r-value';
 
 
 export enum VertexType {
@@ -56,27 +57,22 @@ export interface DataflowGraphVertexAstLink {
 
 /**
  * Marker vertex for a value in the dataflow of the program.
- * This does not contain the _value_ of the referenced constant
- * as this is available with the {@link DataflowGraphVertexBase#id|id} in the {@link NormalizedAst|normalized AST}
- * (or more specifically the {@link AstIdMap}).
- *
- * If you have a {@link DataflowGraph|dataflow graph} named `graph`
- * with an {@link AstIdMap} and a value vertex object with name `value` the following Code should work:
+ * For user-code constants (numbers, strings, logicals) the value is recovered by looking up the
+ * {@link DataflowGraphVertexBase#id|id} in the {@link NormalizedAst|normalized AST}:
  * @example
  * ```ts
  * const node = graph.idMap.get(value.id)
  * ```
  *
- * This then returns the corresponding node in the {@link NormalizedAst|normalized AST}, for example,
- * an {@link RNumber} or {@link RString}.
- *
- * This works similarly for {@link IdentifierReference|identifier references}
- * for which you can use the {@link IdentifierReference#nodeId|`nodeId`}.
+ * For built-in constants whose id is not in the {@link AstIdMap} (e.g. `T` resolving to `built-in:T`),
+ * the abstract {@link Value} is stored directly in the {@link DataflowGraphVertexValue#value|value} field.
  * @see {@link isValueVertex} - to check if a vertex is a value vertex
  */
 export interface DataflowGraphVertexValue extends DataflowGraphVertexBase {
 	readonly tag:          VertexType.Value
 	readonly environment?: undefined
+	/** Pre-computed abstract value; set for built-in constants (e.g. `T`, `F`) whose id is not in the AST id map */
+	readonly value?:       Value
 }
 
 /**

src/dataflow/internal/process/functions/call/built-in/built-in-expression-list.ts

@@ -26,6 +26,8 @@ import { expensiveTrace } from '../../../../../../util/log';
 import type { Writable } from 'ts-essentials';
 import { makeAllMaybe } from '../../../../../environments/reference-to-maybe';
 import { BuiltInProcName } from '../../../../../environments/built-in-proc-name';
+import type { BuiltInIdentifierConstant } from '../../../../../environments/built-in';
+import { valueFromTsValue } from '../../../../../eval/values/general';
 
 
 
@@ -60,6 +62,14 @@ function linkReadNameToWriteIfPossible(read: IdentifierReference, environments:
 		} else {
 			nextGraph.addEdge(rid, tid, EdgeType.Reads);
 		}
+		if(target.type === ReferenceType.BuiltInConstant) {
+			nextGraph.addVertex({
+				tag:   VertexType.Value,
+				id:    tid,
+				cds:   undefined,
+				value: valueFromTsValue((target as BuiltInIdentifierConstant).value)
+			}, environments);
+		}
 	}
 }
 

test/functionality/dataflow/environments/resolve.test.ts

@@ -19,14 +19,21 @@ import { resolveIdToValue, resolveToConstants } from '../../../../src/dataflow/e
 import { contextFromInput } from '../../../../src/project/context/flowr-analyzer-context';
 import { FlowrConfig } from '../../../../src/config';
 
+/** Controls which extra results are accepted in addition to an exact match */
 enum Allow {
-	None = 0,
-	Top = 1,
-	Bottom = 2
+	/** Only the exact expected value is accepted */
+	ExactOnly = 0,
+	/** Also accept top (unknown); use when the analysis may give up */
+	Top       = 1,
+	/** Also accept bottom (unreachable); use when the result may be unreachable */
+	Bottom    = 2
 }
 
+/** Controls how {@link resolveIdToValue} is invoked during tests */
 enum With {
-	Graph,
+	/** Pass only the dataflow graph, no environment is given to the resolver */
+	GraphOnly,
+	/** Pass the full program environment, the normal fully-informed path */
 	Environment
 }
 
@@ -49,8 +56,8 @@ describe.sequential('Resolve', withShell(shell => {
 	}
 
 	function testWithGraphAndEnvironment(name: string, tests: (withWhat: With) => void) {
-		describe(`${name} (Graph)`, () => {
-			tests(With.Graph);
+		describe(`${name} (Graph only)`, () => {
+			tests(With.GraphOnly);
 		});
 
 		describe(`${name} (Environment)`, () => {
@@ -63,7 +70,7 @@ describe.sequential('Resolve', withShell(shell => {
 		identifier: SlicingCriterion,
 		code: string,
 		expectedValues: Value,
-		allow: Allow = Allow.None,
+		allow: Allow = Allow.ExactOnly,
 		withEnv: With = With.Environment
 	): void {
 		const effectiveName = decorateLabelContext(label(name), ['resolve']);
@@ -76,7 +83,7 @@ describe.sequential('Resolve', withShell(shell => {
 			}).allRemainingSteps();
 
 			const resolved = resolveIdToValue(SlicingCriterion.parse(identifier, dataflow.normalize.idMap), {
-				environment: withEnv === With.Environment ? dataflow.dataflow.environment : undefined,
+				environment: withEnv === With.GraphOnly ? undefined : dataflow.dataflow.environment,
 				graph:       dataflow.dataflow.graph,
 				idMap:       dataflow.normalize.idMap,
 				full:        true,
@@ -96,7 +103,7 @@ describe.sequential('Resolve', withShell(shell => {
 		});
 	}
 
-	function testMutate(name: string, line: number, identifier: string, code: string, expected: Value, allow: Allow = Allow.None) {
+	function testMutate(name: string, line: number, identifier: string, code: string, expected: Value, allow: Allow = Allow.ExactOnly) {
 		const distractors: string[] = [
 			`while(FALSE) { ${identifier} <- 0 }`,
 			`if(FALSE) { ${identifier} <- 0 }`,
@@ -210,6 +217,18 @@ describe.sequential('Resolve', withShell(shell => {
 			});
 		});
 	});
+	describe.each<[string, With]>([
+		['Graph only',  With.GraphOnly  ],
+		['Environment', With.Environment],
+	])('Resolve built-in constants (%s)', (_name, resolveWith) => {
+		testResolve('T resolves to true',         '1@T',    'T',             set([true]),  Allow.ExactOnly, resolveWith);
+		testResolve('F resolves to false',        '1@F',    'F',             set([false]), Allow.ExactOnly, resolveWith);
+		testResolve('TRUE resolves to true',      '1@TRUE', 'TRUE',          set([true]),  Allow.ExactOnly, resolveWith);
+		testResolve('T multiple, resolve second', '2@T',    'T\nT\nT',       set([true]),  Allow.ExactOnly, resolveWith);
+		testResolve('T shadow with logical',      '2@T',    'T <- FALSE\nT', set([false]), Allow.ExactOnly, resolveWith);
+		testResolve('T shadow with number',       '2@T',    'T <- 42\nT',    set([42]),    Allow.ExactOnly, resolveWith);
+	});
+
 	describe('Builtin Constants', () => {
 		// Always Resolve
 		test.each([

test/functionality/dataflow/main/atomic/dataflow-atomic.test.ts

@@ -41,6 +41,21 @@ describe.sequential('Atomic (dataflow information)', withShell(shell => {
 		}
 	});
 
+	describe('Built-in constant aliases', () => {
+		for(const [input, capability] of [
+			['T', 'logical'],
+			['F', 'logical'],
+		] as [string, SupportedFlowrCapabilityId][]) {
+			assertDataflow(label(input, [capability]), shell, input,
+				emptyGraph()
+					.use(0, input)
+					.constant(NodeId.toBuiltIn(input), {}, false)
+					.reads(0, NodeId.toBuiltIn(input)),
+				{ expectIsSubgraph: true }
+			);
+		}
+	});
+
 	assertDataflow(label('simple variable', ['name-normal']), shell,
 		'xylophone', emptyGraph().use(0, 'xylophone')
 	);