trust-schema: printESM.Context

yoursunny · Oct 29, 2024 · b255583 · b255583
1 parent 4ebc57f
commit b255583
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Showing 2 changed files with 45 additions and 13 deletions.
diff --git a/pkg/lvs/src/translate.ts b/pkg/lvs/src/translate.ts
@@ -168,7 +168,10 @@ class LvsFilter implements P.VariablePattern.Filter, printESM.PrintableFilter {
     this.func(name.at(0), args);
   }
 
-  public printESM(indent: string): string {
+  public printESM(ctx: printESM.Context): string {
+    const { indent, imports } = ctx;
+    imports.get("./lvsuserfns.mjs").add("* as lvsUserFns");
+
     const lines: string[] = [];
     lines.push(`${indent}{`);
     lines.push(`${indent}  accept(name, vars) {`);
@@ -177,6 +180,7 @@ class LvsFilter implements P.VariablePattern.Filter, printESM.PrintableFilter {
       if (typeof b === "string") {
         lines.push(`${indent}      vars.get(${JSON.stringify(b)})?.get(0),`);
       } else {
+        imports.get("@ndn/packet").add("Component");
         lines.push(`${indent}      Component.from(${JSON.stringify(b.toString())}),`);
       }
     }

diff --git a/pkg/trust-schema/src/schema/print.ts b/pkg/trust-schema/src/schema/print.ts
@@ -1,7 +1,10 @@
+import { DefaultMap } from "mnemonist";
+
 import { AlternatePattern, CertNamePattern, ConcatPattern, ConstPattern, OverlapPattern, type Pattern, VariablePattern } from "./pattern";
 import type { TrustSchemaPolicy } from "./policy";
 
-function printPattern(p: Pattern, indent = ""): string {
+function printPattern(p: Pattern, ctx: printESM.Context): string {
+  const { indent } = ctx;
   if (p instanceof ConstPattern) {
     return `${indent}new P.ConstPattern(${JSON.stringify(p.name.toString())})`;
   }
@@ -14,12 +17,12 @@ function printPattern(p: Pattern, indent = ""): string {
       opts.push(`maxComps: ${p.maxComps}`);
     }
     if (p.inner) {
-      opts.push(`inner: ${printPattern(p.inner, indent).trimStart()}`);
+      opts.push(`inner: ${printPattern(p.inner, ctx).trimStart()}`);
     }
     if (p.filter) {
       const filter = p.filter as Partial<printESM.PrintableFilter>;
       if (typeof filter.printESM === "function") {
-        opts.push(`filter: ${filter.printESM(indent).trimStart()}`);
+        opts.push(`filter: ${filter.printESM(ctx).trimStart()}`);
       } else {
         opts.push(`filter: { accept(name, vars) { throw new Error(${
           JSON.stringify(`cannot translate filter ${p.filter.constructor.name}`)}) } }`);
@@ -32,47 +35,72 @@ function printPattern(p: Pattern, indent = ""): string {
     return `${indent}new P.CertNamePattern()`;
   }
   if (p instanceof ConcatPattern) {
-    return printSequence("ConcatPattern", p.parts, indent);
+    return printSequence("ConcatPattern", p.parts, ctx);
   }
   if (p instanceof AlternatePattern) {
-    return printSequence("AlternatePattern", p.choices, indent);
+    return printSequence("AlternatePattern", p.choices, ctx);
   }
   if (p instanceof OverlapPattern) {
-    return printSequence("OverlapPattern", p.branches, indent);
+    return printSequence("OverlapPattern", p.branches, ctx);
   }
   return `${indent}throw new Error(${
     JSON.stringify(`cannot translate pattern ${p.constructor.name}`)})`;
 }
 
-function printSequence(typ: string, list: Pattern[], indent: string): string {
+function printSequence(typ: string, list: Pattern[], ctx: printESM.Context): string {
+  const { indent } = ctx;
+  const inner = { ...ctx, indent: `  ${indent}` };
   return `${indent}new P.${typ}([\n${
-    list.map((p) => printPattern(p, `  ${indent}`)).join(",\n")
+    list.map((p) => printPattern(p, inner)).join(",\n")
   },\n${indent}])`;
 }
 
 /** Print policy as ECMAScript module. */
 export function printESM(policy: TrustSchemaPolicy): string {
+  const ctx: printESM.Context = {
+    indent: "",
+    imports: new DefaultMap<string, Set<string>>(() => new Set<string>()),
+  };
+  ctx.imports.get("@ndn/trust-schema")
+    .add("TrustSchemaPolicy")
+    .add("pattern as P");
+
   const lines: string[] = [];
   lines.push(
-    "import { TrustSchemaPolicy, pattern as P } from \"@ndn/trust-schema\";",
-    "import { Name, Component } from \"@ndn/packet\";",
     "",
     "export const policy = new TrustSchemaPolicy();",
     "",
   );
   for (const [id, p] of policy.listPatterns()) {
-    lines.push(`policy.addPattern(${JSON.stringify(id)}, ${printPattern(p)});`);
+    lines.push(`policy.addPattern(${JSON.stringify(id)}, ${printPattern(p, ctx)});`);
   }
   lines.push("");
   for (const [packet, signer] of policy.listRules()) {
     lines.push(`policy.addRule(${JSON.stringify(packet)}, ${JSON.stringify(signer)});`);
   }
   lines.push("");
+
+  const pkgs = Array.from(ctx.imports.keys());
+  pkgs.sort((a, b) => -a.localeCompare(b));
+  for (const pkg of pkgs) {
+    const tokens = Array.from(ctx.imports.get(pkg));
+    if (tokens.length === 1 && tokens[0]!.startsWith("* as ")) {
+      lines.unshift(`import ${tokens[0]} from ${JSON.stringify(pkg)};`);
+    } else {
+      tokens.sort((a, b) => a.localeCompare(b));
+      lines.unshift(`import { ${tokens.join(", ")} } from ${JSON.stringify(pkg)};`);
+    }
+  }
   return lines.join("\n");
 }
 
 export namespace printESM {
+  export interface Context {
+    indent: string;
+    imports: DefaultMap<string, Set<string>>;
+  }
+
   export interface PrintableFilter extends VariablePattern.Filter {
-    printESM: (indent: string) => string;
+    printESM: (ctx: Context) => string;
   }
 }