Move printFormula to Formula.stringify and add tests for it

src/game/formulas/formulas.ts

@@ -56,6 +56,7 @@ export abstract class InternalFormula<T extends [FormulaSource] | FormulaSource[
     protected readonly internalIntegrate: IntegrateFunction<T> | undefined;
     protected readonly internalIntegrateInner: IntegrateFunction<T> | undefined;
     protected readonly applySubstitution: SubstitutionFunction<T> | undefined;
+    protected readonly description: string | undefined;
     protected readonly internalVariables: number;
 
     public readonly innermostVariable: ProcessedComputable<DecimalSource> | undefined;
@@ -85,6 +86,7 @@ export abstract class InternalFormula<T extends [FormulaSource] | FormulaSource[
         this.internalIntegrate = readonlyProperties.internalIntegrate;
         this.internalIntegrateInner = readonlyProperties.internalIntegrateInner;
         this.applySubstitution = readonlyProperties.applySubstitution;
+        this.description = options.description;
     }
 
     private setupVariable({
@@ -216,6 +218,25 @@ export abstract class InternalFormula<T extends [FormulaSource] | FormulaSource[
         return new Formula({ variable: value });
     }
 
+    /**
+     * Stringifies the formula so it's more easy to read in the console
+     * @param formula The formula source to print, used for mapping inputs
+     */
+    public static stringify(formula: FormulaSource): string {
+        if (formula instanceof InternalFormula) {
+            if (formula.description != null) {
+                return formula.description;
+            }
+            if (formula.internalEvaluate == null) {
+                return formula.hasVariable() ? "x" : format(formula.inputs[0] ?? 0);
+            }
+            return `${formula.internalEvaluate.name}(${formula.inputs
+                .map(Formula.stringify)
+                .join(", ")})`;
+        }
+        return format(unref(formula));
+    }
+
     // TODO add integration support to step-wise functions
     /**
      * Creates a step-wise formula. After {@link start} the formula will have an additional modifier.
@@ -256,7 +277,9 @@ export abstract class InternalFormula<T extends [FormulaSource] | FormulaSource[
         return new Formula({
             inputs: [value],
             evaluate: evalStep,
-            invert: formula.isInvertible() && formula.hasVariable() ? invertStep : undefined
+            invert: formula.isInvertible() && formula.hasVariable() ? invertStep : undefined,
+            // Can't do anything more descriptive, due to formula's input always being a variable
+            description: "indeterminate"
         });
     }
 
@@ -309,7 +332,9 @@ export abstract class InternalFormula<T extends [FormulaSource] | FormulaSource[
         return new Formula({
             inputs: [value],
             evaluate: evalStep,
-            invert: formula.isInvertible() && formula.hasVariable() ? invertStep : undefined
+            invert: formula.isInvertible() && formula.hasVariable() ? invertStep : undefined,
+            // Can't do anything more descriptive, due to formula's input always being a variable
+            description: "indeterminate"
         });
     }
     public static conditional(
@@ -878,6 +903,10 @@ export abstract class InternalFormula<T extends [FormulaSource] | FormulaSource[
         });
     }
 
+    public stringify() {
+        return Formula.stringify(this);
+    }
+
     public step(
         start: Computable<DecimalSource>,
         formulaModifier: (value: InvertibleIntegralFormula) => GenericFormula
@@ -1402,28 +1431,6 @@ export function findNonInvertible(formula: GenericFormula): GenericFormula | nul
     return null;
 }
 
-/**
- * Stringifies a formula so it's more easy to read in the console
- * @param formula The formula to print
- */
-export function printFormula(formula: FormulaSource): string {
-    if (formula instanceof InternalFormula) {
-        // eslint-disable-next-line @typescript-eslint/ban-ts-comment
-        // @ts-ignore
-        return formula.internalEvaluate == null
-            ? formula.hasVariable()
-                ? "x"
-                : formula.inputs[0] ?? 0
-            : // eslint-disable-next-line @typescript-eslint/ban-ts-comment
-              // @ts-ignore
-              formula.internalEvaluate.name +
-                  "(" +
-                  formula.inputs.map(printFormula).join(", ") +
-                  ")";
-    }
-    return format(unref(formula));
-}
-
 /**
  * Utility for calculating the maximum amount of purchases possible with a given formula and resource. If {@link cumulativeCost} is changed to false, the calculation will be much faster with higher numbers.
  * @param formula The formula to use for calculating buy max from

src/game/formulas/types.d.ts

@@ -37,9 +37,13 @@ type SubstitutionFunction<T> = (
     ...inputs: T
 ) => GenericFormula;
 
-type VariableFormulaOptions = { variable: ProcessedComputable<DecimalSource> };
+type VariableFormulaOptions = {
+    variable: ProcessedComputable<DecimalSource>;
+    description?: string;
+};
 type ConstantFormulaOptions = {
     inputs: [FormulaSource];
+    description?: string;
 };
 type GeneralFormulaOptions<T extends [FormulaSource] | FormulaSource[]> = {
     inputs: T;
@@ -48,6 +52,7 @@ type GeneralFormulaOptions<T extends [FormulaSource] | FormulaSource[]> = {
     integrate?: IntegrateFunction<T>;
     integrateInner?: IntegrateFunction<T>;
     applySubstitution?: SubstitutionFunction<T>;
+    description?: string;
 };
 type FormulaOptions<T extends [FormulaSource] | FormulaSource[]> =
     | VariableFormulaOptions
@@ -63,6 +68,7 @@ type InternalFormulaProperties<T extends [FormulaSource] | FormulaSource[]> = {
     internalIntegrateInner?: IntegrateFunction<T>;
     applySubstitution?: SubstitutionFunction<T>;
     innermostVariable?: ProcessedComputable<DecimalSource>;
+    description?: string;
 };
 
 type SubstitutionStack = ((value: GenericFormula) => GenericFormula)[] | undefined;

tests/game/formulas.test.ts

@@ -155,7 +155,7 @@ describe("Formula Equality Checking", () => {
     describe("Formula aliases", () => {
         function testAliases<T extends FormulaFunctions>(
             aliases: T[],
-            args: Parameters<typeof Formula[T]>
+            args: Parameters<(typeof Formula)[T]>
         ) {
             describe(aliases[0], () => {
                 let formula: GenericFormula;
@@ -250,7 +250,7 @@ describe("Creating Formulas", () => {
 
     function checkFormula<T extends FormulaFunctions>(
         functionName: T,
-        args: Readonly<Parameters<typeof Formula[T]>>
+        args: Readonly<Parameters<(typeof Formula)[T]>>
     ) {
         let formula: GenericFormula;
         beforeAll(() => {
@@ -274,7 +274,7 @@ describe("Creating Formulas", () => {
     // It's a lot of tests, but I'd rather be exhaustive
     function testFormulaCall<T extends FormulaFunctions>(
         functionName: T,
-        args: Readonly<Parameters<typeof Formula[T]>>
+        args: Readonly<Parameters<(typeof Formula)[T]>>
     ) {
         if ((functionName === "slog" || functionName === "layeradd") && args[0] === -1) {
             // These cases in particular take a long time, so skip them
@@ -1275,3 +1275,16 @@ describe("Buy Max", () => {
         });
     });
 });
+
+describe("Stringifies", () => {
+    test("Nested formula", () => {
+        const variable = Formula.variable(ref(0));
+        expect(variable.add(5).pow(Formula.constant(10)).stringify()).toBe(
+            "pow(add(x, 5.00), 10.00)"
+        );
+    });
+    test("Indeterminate", () => {
+        expect(Formula.if(10, true, f => f.add(5)).stringify()).toBe("indeterminate");
+        expect(Formula.step(10, 5, f => f.add(5)).stringify()).toBe("indeterminate");
+    });
+});

tests/game/modifiers.test.ts

@@ -1,5 +1,5 @@
 import { CoercableComponent, JSXFunction } from "features/feature";
-import Formula, { printFormula } from "game/formulas/formulas";
+import Formula from "game/formulas/formulas";
 import {
     createAdditiveModifier,
     createExponentialModifier,
@@ -52,7 +52,7 @@ function testModifiers<
             expect(modifier.invert(operation(10, 5))).compare_tolerance(10));
         test("getFormula returns the right formula", () => {
             const value = ref(10);
-            expect(printFormula(modifier.getFormula(Formula.variable(value)))).toBe(
+            expect(modifier.getFormula(Formula.variable(value)).stringify()).toBe(
                 `${operation.name}(x, 5.00)`
             );
         });
@@ -156,7 +156,7 @@ describe("Sequential Modifiers", () => {
             expect(modifier.invert(Decimal.add(10, 5).times(5).pow(5))).compare_tolerance(10));
         test("getFormula returns the right formula", () => {
             const value = ref(10);
-            expect(printFormula(modifier.getFormula(Formula.variable(value)))).toBe(
+            expect(modifier.getFormula(Formula.variable(value)).stringify()).toBe(
                 `pow(mul(add(x, 5.00), 5.00), 5.00)`
             );
         });