add jq filter to ValueSchemaError

dist-deno/libs/ValueSchemaError.ts

@@ -1,4 +1,4 @@
-import { Key, Values } from "./types.ts";
+import { isNumber, Key, Values } from "./types.ts";
 export const RULE = {
     TYPE: "type",
     UNDEFINED: "undefined",
@@ -21,6 +21,7 @@ export class ValueSchemaError extends Error {
     /** the rule that input value didn't satisfy */
     public readonly rule: RULE;
     public readonly value: unknown;
+    public readonly filter: string;
     public readonly keyStack: Key[];
     /**
      * throw an error
@@ -47,10 +48,43 @@ export class ValueSchemaError extends Error {
      * @param keyStack path to key that caused error
      */
     constructor(rule: RULE, value: unknown, keyStack: Key[]) {
-        super(`${rule}; ${value}; ${keyStack}`);
+        const filter = buildFilter(keyStack);
+        super(`rule=${rule}; value=${value}; filter=${filter}`);
         this.name = "ValueSchemaError";
         this.rule = rule;
         this.value = value;
+        this.filter = filter;
         this.keyStack = [...keyStack];
     }
 }
+/**
+ * build ilter of `jq` command
+ * @param keyStack key stack; array of property(string) or index(number)
+ * @returns `jq` filter
+ * @see {@link https://jqlang.github.io/jq/manual/ jq manual}
+ * @example
+ * // returns '.foo[1]."bar baz"'
+ * const filter = buildJqFilter(["foo", 1, "bar baz"]);
+ */
+function buildFilter(keyStack: Key[]): string {
+    const REGEXP_ID = /^\w+$/;
+    let filter = "";
+    for (const key of keyStack) {
+        if (isNumber(key)) {
+            // index
+            filter += `[${key}]`;
+            continue;
+        }
+        if (REGEXP_ID.test(key)) {
+            // property that doesn't need to be quoted
+            filter += `.${key}`;
+            continue;
+        }
+        // other property; quote by JSON.stringify()
+        filter += `.${JSON.stringify(key)}`;
+    }
+    if (!filter.startsWith(".")) {
+        filter = `.${filter}`;
+    }
+    return filter;
+}

src/libs/ValueSchemaError.ts

@@ -1,4 +1,4 @@
-import {Key, Values} from "./types";
+import {isNumber, Key, Values} from "./types";
 
 export const RULE =
 {
@@ -28,6 +28,7 @@ export class ValueSchemaError extends Error
 	/** the rule that input value didn't satisfy */
 	public readonly rule: RULE;
 	public readonly value: unknown;
+	public readonly filter: string;
 	public readonly keyStack: Key[];
 
 	/**
@@ -60,11 +61,51 @@ export class ValueSchemaError extends Error
 	 */
 	constructor(rule: RULE, value: unknown, keyStack: Key[])
 	{
-		super(`${rule}; ${value}; ${keyStack}`);
+		const filter = buildFilter(keyStack);
+		super(`rule=${rule}; value=${value}; filter=${filter}`);
 
 		this.name = "ValueSchemaError";
 		this.rule = rule;
 		this.value = value;
+		this.filter = filter;
 		this.keyStack = [...keyStack];
 	}
 }
+
+/**
+ * build ilter of `jq` command
+ * @param keyStack key stack; array of property(string) or index(number)
+ * @returns `jq` filter
+ * @see {@link https://jqlang.github.io/jq/manual/ jq manual}
+ * @example
+ * // returns '.foo[1]."bar baz"'
+ * const filter = buildJqFilter(["foo", 1, "bar baz"]);
+ */
+function buildFilter(keyStack: Key[]): string
+{
+	const REGEXP_ID = /^\w+$/;
+	let filter = "";
+	for(const key of keyStack)
+	{
+		if(isNumber(key))
+		{
+			// index
+			filter += `[${key}]`;
+			continue;
+		}
+		if(REGEXP_ID.test(key))
+		{
+			// property that doesn't need to be quoted
+			filter += `.${key}`;
+			continue;
+		}
+
+		// other property; quote by JSON.stringify()
+		filter += `.${JSON.stringify(key)}`;
+	}
+	if(!filter.startsWith("."))
+	{
+		filter = `.${filter}`;
+	}
+	return filter;
+}