/**
* Unit tests for Error Handling and Edge Cases
* Tests various error conditions and boundary cases
*/
import { describe, expect } from "vitest";
import { z } from "zod";
describe("Error Handling and Edge Cases", () => {
describe("Process Management Errors", () => {
it("should handle SWI-Prolog not installed", () => {
const errorMessage = "SWI-Prolog not found in PATH";
const processError = new Error(errorMessage);
expect(processError.message).toBe(errorMessage);
expect(processError).toBeInstanceOf(Error);
});
it("should handle process spawn failures", () => {
const spawnError = new Error("Failed to spawn process");
expect(() => {
// Simulate a spawn failure scenario
throw spawnError;
}).toThrow(spawnError);
});
it("should handle process communication failures", () => {
const communicationError = "Process communication failed";
const mockError = new Error(communicationError);
expect(mockError.message).toContain("communication");
});
it("should handle unexpected process termination", () => {
const terminationError = "Process terminated unexpectedly";
expect(typeof terminationError).toBe("string");
expect(terminationError).toContain("terminated");
});
});
describe("Query Timeout Handling", () => {
it("should timeout long-running queries", async () => {
const timeoutMs = 5000;
const startTime = Date.now();
// Simulate a query that times out
const timeoutPromise = new Promise((_, reject) => {
setTimeout(() => {
reject(new Error("Query timeout"));
}, timeoutMs);
});
try {
await timeoutPromise;
} catch (error) {
const elapsed = Date.now() - startTime;
expect(error).toBeInstanceOf(Error);
expect((error as Error).message).toBe("Query timeout");
expect(elapsed).toBeGreaterThanOrEqual(timeoutMs);
}
});
it("should handle timeout cleanup properly", () => {
const timeoutId = setTimeout(() => { }, 1000);
clearTimeout(timeoutId);
// Verify cleanup doesn't throw
expect(() => clearTimeout(timeoutId)).not.toThrow();
});
});
describe("File System Error Handling", () => {
it("should handle file not found errors", () => {
const filename = "nonexistent.pl";
const fileError = new Error(`ENOENT: no such file or directory, open '${filename}'`);
expect(fileError.message).toContain("ENOENT");
expect(fileError.message).toContain(filename);
});
it("should handle permission denied errors", () => {
const filename = "protected.pl";
const permissionError = new Error(`EACCES: permission denied, open '${filename}'`);
expect(permissionError.message).toContain("EACCES");
expect(permissionError.message).toContain("permission denied");
});
it("should handle directory access errors", () => {
const invalidPath = "/invalid/path/file.pl";
const pathError = new Error(`Path does not exist: ${invalidPath}`);
expect(pathError.message).toContain(invalidPath);
});
});
describe("Prolog Syntax Error Handling", () => {
it("should handle invalid Prolog syntax", () => {
const invalidQuery = "this is not valid prolog syntax !!!";
const syntaxError = `Syntax error in query: ${invalidQuery}`;
expect(syntaxError).toContain("Syntax error");
expect(syntaxError).toContain(invalidQuery);
});
it("should handle malformed facts", () => {
const malformedFact = "parent(john, mary"; // Missing closing parenthesis
const factError = `Malformed fact: ${malformedFact}`;
expect(factError).toContain("Malformed fact");
expect(factError).toContain(malformedFact);
});
it("should handle undefined predicates", () => {
const undefinedPredicate = "unknown_predicate(X)";
const predicateError = `Undefined predicate: ${undefinedPredicate}`;
expect(predicateError).toContain("Undefined predicate");
});
});
describe("Input Validation Edge Cases", () => {
it("should handle extremely long filenames", () => {
const longFilename = "a".repeat(300) + ".pl";
const filenameSchema = z.string().max(255);
const result = filenameSchema.safeParse(longFilename);
expect(result.success).toBe(false);
});
it("should handle empty string inputs", () => {
const emptySchema = z.string().min(1);
expect(emptySchema.safeParse("").success).toBe(false);
expect(emptySchema.safeParse(" ").success).toBe(true); // Whitespace is allowed
});
it("should handle special characters in queries", () => {
const specialCharQuery = "test('special chars: äöü@#$%^&*()')";
expect(typeof specialCharQuery).toBe("string");
expect(specialCharQuery).toContain("special chars");
});
it("should handle very long queries", () => {
const longQuery = "test(" + "a".repeat(10000) + ")";
const querySchema = z.string().max(5000);
const result = querySchema.safeParse(longQuery);
expect(result.success).toBe(false);
});
});
describe("Memory and Resource Management", () => {
it("should handle memory exhaustion gracefully", () => {
const memoryError = new Error("Insufficient memory");
expect(memoryError.message).toBe("Insufficient memory");
});
it("should handle resource cleanup on shutdown", () => {
const cleanupFunctions = [
() => console.log("Cleaning up process"),
() => console.log("Cleaning up files"),
() => console.log("Cleaning up connections"),
];
expect(cleanupFunctions).toHaveLength(3);
cleanupFunctions.forEach((fn) => {
expect(typeof fn).toBe("function");
});
});
});
describe("Concurrency and Race Conditions", () => {
it("should handle multiple simultaneous queries", async () => {
const queries = ["query1(X)", "query2(Y)", "query3(Z)"];
const promises = queries.map(
(query) =>
new Promise((resolve) => {
setTimeout(() => resolve(`Result for ${query}`), Math.random() * 100);
}),
);
const results = await Promise.all(promises);
expect(results).toHaveLength(3);
results.forEach((result) => {
expect(typeof result).toBe("string");
});
});
it("should handle query queue management", () => {
const queryQueue: string[] = [];
const maxQueueSize = 10;
for (let i = 0; i < 15; i++) {
if (queryQueue.length < maxQueueSize) {
queryQueue.push(`query${i}`);
}
}
expect(queryQueue).toHaveLength(maxQueueSize);
});
});
describe("Network and I/O Errors", () => {
it("should handle stdin/stdout communication errors", () => {
const ioError = new Error("Broken pipe");
expect(ioError.message).toBe("Broken pipe");
expect(ioError).toBeInstanceOf(Error);
});
it("should handle process signal interruption", () => {
const signals = ["SIGTERM", "SIGINT", "SIGKILL"];
signals.forEach((signal) => {
expect(typeof signal).toBe("string");
expect(signal).toMatch(/^SIG/);
});
});
});
describe("Edge Case Queries", () => {
it("should handle queries with no solutions", () => {
const noSolutionQuery = "impossible_predicate(X)";
const expectedResult = "false";
expect(typeof noSolutionQuery).toBe("string");
expect(expectedResult).toBe("false");
});
it("should handle queries with infinite solutions", () => {
const infiniteQuery = "member(X, [1,2,3|_])";
expect(typeof infiniteQuery).toBe("string");
expect(infiniteQuery).toContain("member");
});
it("should handle recursive queries that might stack overflow", () => {
const recursiveQuery = "ancestor(X, Y) :- ancestor(X, Z), ancestor(Z, Y)";
expect(typeof recursiveQuery).toBe("string");
expect(recursiveQuery).toContain("ancestor");
});
});
describe("Tool-specific Error Cases", () => {
it("should handle consult_file with binary files", () => {
const binaryFile = "image.jpg";
const binaryError = `Cannot consult binary file: ${binaryFile}`;
expect(binaryError).toContain("binary file");
});
it("should handle assert with complex terms", () => {
const complexFact = "complex(term(with(nested(structures))))";
expect(typeof complexFact).toBe("string");
expect(complexFact).toContain("nested");
});
it("should handle retract with non-existent clauses", () => {
const nonExistentFact = "does_not_exist(anywhere)";
const retractError = `Cannot retract non-existent clause: ${nonExistentFact}`;
expect(retractError).toContain("non-existent clause");
});
});
});
