MACHIN

32/node_modules/jake/lib/rule.js

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+let path = require('path');
+let fs = require('fs');
+let Task = require('./task/task').Task;
+
+// Split a task to two parts, name space and task name.
+// For example, given 'foo:bin/a%.c', return an object with
+// - 'ns'     : foo
+// - 'name'   : bin/a%.c
+function splitNs(task) {
+  let parts = task.split(':');
+  let name = parts.pop();
+  let ns = resolveNs(parts);
+  return {
+    'name' : name,
+    'ns'   : ns
+  };
+}
+
+// Return the namespace based on an array of names.
+// For example, given ['foo', 'baz' ], return the namespace
+//
+//   default -> foo -> baz
+//
+// where default is the global root namespace
+// and -> means child namespace.
+function resolveNs(parts) {
+  let  ns = jake.defaultNamespace;
+  for(let i = 0, l = parts.length; ns && i < l; i++) {
+    ns = ns.childNamespaces[parts[i]];
+  }
+  return ns;
+}
+
+// Given a pattern p, say 'foo:bin/a%.c'
+// Return an object with
+// - 'ns'     : foo
+// - 'dir'    : bin
+// - 'prefix' : a
+// - 'suffix' : .c
+function resolve(p) {
+  let task = splitNs(p);
+  let name  = task.name;
+  let ns    = task.ns;
+  let split = path.basename(name).split('%');
+  return {
+    ns: ns,
+    dir: path.dirname(name),
+    prefix: split[0],
+    suffix: split[1]
+  };
+}
+
+// Test whether string a is a suffix of string b
+function stringEndWith(a, b) {
+  let l;
+  return (l = b.lastIndexOf(a)) == -1 ? false : l + a.length == b.length;
+}
+
+// Replace the suffix a of the string s with b.
+// Note that, it is assumed a is a suffix of s.
+function stringReplaceSuffix(s, a, b) {
+  return s.slice(0, s.lastIndexOf(a)) + b;
+}
+
+class Rule {
+  constructor(opts) {
+    this.pattern = opts.pattern;
+    this.source = opts.source;
+    this.prereqs = opts.prereqs;
+    this.action = opts.action;
+    this.opts = opts.opts;
+    this.desc =  opts.desc;
+    this.ns = opts.ns;
+  }
+
+  // Create a file task based on this rule for the specified
+  // task-name
+  // ======
+  // FIXME: Right now this just throws away any passed-in args
+  // for the synthsized task (taskArgs param)
+  // ======
+  createTask(fullName, level) {
+    let self = this;
+    let pattern;
+    let source;
+    let action;
+    let opts;
+    let prereqs;
+    let valid;
+    let src;
+    let tNs;
+    let createdTask;
+    let name = Task.getBaseTaskName(fullName);
+    let nsPath = Task.getBaseNamespacePath(fullName);
+    let ns = this.ns.resolveNamespace(nsPath);
+
+    pattern = this.pattern;
+    source = this.source;
+
+    if (typeof source == 'string') {
+      src = Rule.getSource(name, pattern, source);
+    }
+    else {
+      src = source(name);
+    }
+
+    // TODO: Write a utility function that appends a
+    // taskname to a namespace path
+    src = nsPath.split(':').filter(function (item) {
+      return !!item;
+    }).concat(src).join(':');
+
+    // Generate the prerequisite for the matching task.
+    //    It is the original prerequisites plus the prerequisite
+    //    representing source file, i.e.,
+    //
+    //      rule( '%.o', '%.c', ['some.h'] ...
+    //
+    //    If the objective is main.o, then new task should be
+    //
+    //      file( 'main.o', ['main.c', 'some.h' ] ...
+    prereqs = this.prereqs.slice(); // Get a copy to work with
+    prereqs.unshift(src);
+
+    // Prereq should be:
+    // 1. an existing task
+    // 2. an existing file on disk
+    // 3. a valid rule (i.e., not at too deep a level)
+    valid = prereqs.some(function (p) {
+      let ns = self.ns;
+      return ns.resolveTask(p) ||
+        fs.existsSync(Task.getBaseTaskName(p)) ||
+        jake.attemptRule(p, ns, level + 1);
+    });
+
+    // If any of the prereqs aren't valid, the rule isn't valid
+    if (!valid) {
+      return null;
+    }
+    // Otherwise, hunky-dory, finish creating the task for the rule
+    else {
+      // Create the action for the task
+      action = function () {
+        let task = this;
+        self.action.apply(task);
+      };
+
+      opts = this.opts;
+
+      // Insert the file task into Jake
+      //
+      // Since createTask function stores the task as a child task
+      // of currentNamespace. Here we temporariliy switch the namespace.
+      // FIXME: Should allow optional ns passed in instead of this hack
+      tNs = jake.currentNamespace;
+      jake.currentNamespace = ns;
+      createdTask = jake.createTask('file', name, prereqs, action, opts);
+      createdTask.source = src.split(':').pop();
+      jake.currentNamespace = tNs;
+
+      return createdTask;
+    }
+  }
+
+  match(name) {
+    return Rule.match(this.pattern, name);
+  }
+
+  // Test wether the a prerequisite matchs the pattern.
+  // The arg 'pattern' does not have namespace as prefix.
+  // For example, the following tests are true
+  //
+  //   pattern      |    name
+  //   bin/%.o      |    bin/main.o
+  //   bin/%.o      |    foo:bin/main.o
+  //
+  // The following tests are false (trivally)
+  //
+  //   pattern      |    name
+  //   bin/%.o      |    foobin/main.o
+  //   bin/%.o      |    bin/main.oo
+  static match(pattern, name) {
+    let p;
+    let task;
+    let obj;
+    let filename;
+
+    if (pattern instanceof RegExp) {
+      return pattern.test(name);
+    }
+    else if (pattern.indexOf('%') == -1) {
+      // No Pattern. No Folder. No Namespace.
+      // A Simple Suffix Rule. Just test suffix
+      return stringEndWith(pattern, name);
+    }
+    else {
+      // Resolve the dir, prefix and suffix of pattern
+      p = resolve(pattern);
+
+      // Resolve the namespace and task-name
+      task = splitNs(name);
+      name = task.name;
+
+      // Set the objective as the task-name
+      obj = name;
+
+      // Namespace is already matched.
+
+      // Check dir
+      if (path.dirname(obj) != p.dir) {
+        return false;
+      }
+
+      filename = path.basename(obj);
+
+      // Check file name length
+      if ((p.prefix.length + p.suffix.length + 1) > filename.length) {
+        // Length does not match.
+        return false;
+      }
+
+      // Check prefix
+      if (filename.indexOf(p.prefix) !== 0) {
+        return false;
+      }
+
+      // Check suffix
+      if (!stringEndWith(p.suffix, filename)) {
+        return false;
+      }
+
+      // OK. Find a match.
+      return true;
+    }
+  }
+
+  // Generate the source based on
+  //  - name    name for the synthesized task
+  //  - pattern    pattern for the objective
+  //  - source    pattern for the source
+  //
+  // Return the source with properties
+  //  - dep      the prerequisite of source
+  //             (with the namespace)
+  //
+  //  - file     the file name of source
+  //             (without the namespace)
+  //
+  // For example, given
+  //
+  //  - name   foo:bin/main.o
+  //  - pattern    bin/%.o
+  //  - source    src/%.c
+  //
+  //    return 'foo:src/main.c',
+  //
+  static getSource(name, pattern, source) {
+    let dep;
+    let pat;
+    let match;
+    let file;
+    let src;
+
+    // Regex pattern -- use to look up the extension
+    if (pattern instanceof RegExp) {
+      match = pattern.exec(name);
+      if (match) {
+        if (typeof source == 'function') {
+          src = source(name);
+        }
+        else {
+          src = stringReplaceSuffix(name, match[0], source);
+        }
+      }
+    }
+    // Assume string
+    else {
+      // Simple string suffix replacement
+      if (pattern.indexOf('%') == -1) {
+        if (typeof source == 'function') {
+          src = source(name);
+        }
+        else {
+          src = stringReplaceSuffix(name, pattern, source);
+        }
+      }
+      // Percent-based substitution
+      else {
+        pat = pattern.replace('%', '(.*?)');
+        pat = new RegExp(pat);
+        match = pat.exec(name);
+        if (match) {
+          if (typeof source == 'function') {
+            src = source(name);
+          }
+          else {
+            file = match[1];
+            file = source.replace('%', file);
+            dep = match[0];
+            src = name.replace(dep, file);
+          }
+        }
+      }
+    }
+
+    return src;
+  }
+}
+
+
+exports.Rule = Rule;