feat: add pretty print support

Signed-off-by: Gordon Smith <[email protected]>

Author: Copilot

.gitattributes

@@ -1,3 +1,10 @@
-# Set default behavior to automatically normalize line endings.
+*.wit text eol=lf
+*.snap text eol=lf
+*.ts text eol=lf
+*.json text eol=lf
+*.mjs text eol=lf
+Cargo.toml text eol=lf
+README.md text eol=lf
+LICENSE text eol=lf# Set default behavior to automatically normalize line endings.
 * text=auto
 

package.json

@@ -181,6 +181,11 @@
                 "command": "wit-idl.extractCoreWasm",
                 "title": "Extract Core Wasm",
                 "category": "WIT"
+            },
+            {
+                "command": "wit-idl.formatDocument",
+                "title": "Format Document",
+                "category": "WIT"
             }
         ],
         "submenus": [
@@ -196,6 +201,11 @@
                     "when": "resourceExtname == .wit",
                     "group": "navigation"
                 },
+                {
+                    "command": "wit-idl.formatDocument",
+                    "when": "resourceExtname == .wit",
+                    "group": "1_modification@10"
+                },
                 {
                     "submenu": "wit-idl.generateBindings.submenu",
                     "when": "resourceExtname == .wit || witIdl.isWasmComponent",
@@ -289,6 +299,10 @@
                 {
                     "command": "wit-idl.extractCoreWasm",
                     "when": "witIdl.isWasmComponent"
+                },
+                {
+                    "command": "wit-idl.formatDocument",
+                    "when": "editorLangId == wit"
                 }
             ]
         },
@@ -301,6 +315,11 @@
             {
                 "command": "wit-idl.syntaxCheckWorkspace",
                 "key": "shift+f7"
+            },
+            {
+                "command": "wit-idl.formatDocument",
+                "key": "shift+alt+f",
+                "when": "editorTextFocus && editorLangId == wit"
             }
         ],
         "customEditors": [

scripts/format-test-wit-files.js

@@ -0,0 +1,177 @@
+#!/usr/bin/env node
+import fs from "node:fs";
+import path from "node:path";
+
+function replaceAllSeq(line, replacements) {
+    let out = line;
+    for (const [re, repl] of replacements) out = out.replace(re, repl);
+    return out;
+}
+function ensureSemicolon(line) {
+    return line.replace(/\s*;\s*$/, ";");
+}
+function collapseSpaces(line) {
+    return line.replace(/\s+/g, " ");
+}
+
+function isOpeningBrace(line) {
+    return line.endsWith("{") && !line.includes("}");
+}
+
+function formatFunc(line) {
+    const replacements = [
+        [/:func/, ": func"],
+        [/:\s*func/, ": func"],
+        [/func\s*\(/, "func("],
+        [/\)\s*->\s*/, ") -> "],
+        [/\)->\s*/, ") -> "],
+        [/\)->/, ") -> "],
+        [/,\s*/g, ", "],
+        [/:\s*/g, ": "],
+    ];
+    return ensureSemicolon(replaceAllSeq(line, replacements));
+}
+function formatPackage(line) {
+    return ensureSemicolon(collapseSpaces(line));
+}
+function formatNamedBlock(line) {
+    return collapseSpaces(line).replace(/\s*{\s*$/, " {");
+}
+function formatImportExport(line) {
+    const base = line.replace(/^(import|export)\s+/, "$1 ");
+    return base.includes(": func") || base.includes(":func") ? formatFunc(base) : ensureSemicolon(base);
+}
+function formatUse(line) {
+    const repl = [
+        [/^use\s+/, "use "],
+        [/\s+as\s+/, " as "],
+        [/\s+from\s+/, " from "],
+    ];
+    return ensureSemicolon(replaceAllSeq(line, repl));
+}
+function formatTypeAlias(line) {
+    const repl = [
+        [/^type\s+/, "type "],
+        [/\s*=\s*/, " = "],
+    ];
+    return ensureSemicolon(replaceAllSeq(line, repl));
+}
+function formatField(line) {
+    return replaceAllSeq(line, [
+        [/::?/g, (m) => (m.endsWith(":") ? ": " : m)],
+        [/:\s*/g, ": "],
+        [/,\s*/g, ", "],
+        [/,\s*$/, ","],
+    ]);
+}
+function isTypeDecl(line) {
+    return /^(record|variant|enum|flags|resource)\s+/.test(line);
+}
+function isFuncDecl(line) {
+    if (line.startsWith("import ") || line.startsWith("export ")) return false;
+    return /^[a-zA-Z][\w-]*\s*:\s*func\b/.test(line) || /:\s*func\b/.test(line) || /->/.test(line);
+}
+function isFieldDecl(line) {
+    const t = line.trim();
+    return /^[a-zA-Z][a-zA-Z0-9-]*\s*[:,(]/.test(t) || /^[a-zA-Z][a-zA-Z0-9-]*\s*,?\s*$/.test(t);
+}
+
+function formatLine(line) {
+    if (line.startsWith("package ")) return formatPackage(line);
+    if (line.startsWith("interface ")) return formatNamedBlock(line);
+    if (line.startsWith("world ")) return formatNamedBlock(line);
+    if (isTypeDecl(line)) return formatNamedBlock(line);
+    if (line.startsWith("type ") && line.includes("=")) return formatTypeAlias(line);
+    if (isFuncDecl(line)) return formatFunc(line);
+    if (line.startsWith("import ") || line.startsWith("export ")) return formatImportExport(line);
+    if (line.startsWith("use ")) return formatUse(line);
+    if (isFieldDecl(line)) return formatField(line);
+    return line;
+}
+
+function formatContent(content, tabSize = 2, insertSpaces = true) {
+    const indentUnit = insertSpaces ? " ".repeat(tabSize) : "\t";
+    const lines = content.split(/\r?\n/);
+    const out = [];
+    let indentLevel = 0;
+    let inMultiLineTupleAlias = false;
+    let aliasGenericDepth = 0;
+    let inFuncParams = false;
+    for (let i = 0; i < lines.length; i++) {
+        const raw = lines[i];
+        const trimmed = raw.trim();
+        if (trimmed === "") {
+            out.push("");
+            continue;
+        }
+        if (/^\}/.test(trimmed)) indentLevel = Math.max(0, indentLevel - 1);
+        if (/^\/\//.test(trimmed)) {
+            const extra = inMultiLineTupleAlias && aliasGenericDepth > 0 && !/^>>/.test(trimmed) ? 1 : 0;
+            out.push(indentUnit.repeat(indentLevel + extra) + trimmed);
+            continue;
+        }
+        const formattedLine = formatLine(trimmed);
+        const needsTupleExtra = inMultiLineTupleAlias && aliasGenericDepth > 0 && !/^>>/.test(trimmed);
+        const needsFuncParamExtra = inFuncParams && !/^\)/.test(trimmed);
+        out.push(
+            indentUnit.repeat(indentLevel + (needsTupleExtra ? 1 : 0) + (needsFuncParamExtra ? 1 : 0)) + formattedLine
+        );
+        if (isOpeningBrace(trimmed)) indentLevel++;
+        if (!inFuncParams && /func\($/.test(trimmed)) {
+            let lookahead = i + 1;
+            let activate = true;
+            while (lookahead < lines.length) {
+                const laTrim = lines[lookahead].trim();
+                if (laTrim === "") {
+                    lookahead++;
+                    continue;
+                }
+                if (/^\/\//.test(laTrim)) {
+                    activate = false;
+                }
+                break;
+            }
+            if (activate) inFuncParams = true;
+        } else if (inFuncParams && /^\)/.test(trimmed)) {
+            inFuncParams = false;
+        }
+        if (!inMultiLineTupleAlias && /^type\s+[^=]+=.*tuple<\s*$/.test(trimmed)) {
+            inMultiLineTupleAlias = true;
+            aliasGenericDepth = (trimmed.match(/</g) || []).length - (trimmed.match(/>/g) || []).length;
+        } else if (inMultiLineTupleAlias) {
+            const opens = (trimmed.match(/</g) || []).length;
+            const closes = (trimmed.match(/>/g) || []).length;
+            aliasGenericDepth += opens - closes;
+            if (aliasGenericDepth <= 0) inMultiLineTupleAlias = false;
+        }
+    }
+    return out.join("\n");
+}
+
+function walk(dir, acc) {
+    for (const entry of fs.readdirSync(dir)) {
+        const full = path.join(dir, entry);
+        const stat = fs.statSync(full);
+        if (stat.isDirectory()) walk(full, acc);
+        else if (entry.endsWith(".wit")) acc.push(full);
+    }
+    return acc;
+}
+
+const root = path.resolve("tests");
+if (!fs.existsSync(root)) {
+    console.error("tests directory not found");
+    process.exit(1);
+}
+const files = walk(root, []);
+let changed = 0;
+for (const f of files) {
+    const original = fs.readFileSync(f, "utf8");
+    const formatted = formatContent(original);
+    if (formatted !== original) {
+        fs.writeFileSync(f, formatted, "utf8");
+        changed++;
+        console.log("Formatted", path.relative(process.cwd(), f));
+    }
+}
+console.log(`Processed ${files.length} .wit files. Changed ${changed}.`);