From 3a20fd165f1cdefe16e253c13345924d324de38a Mon Sep 17 00:00:00 2001
From: Jonas Jenwald <jonas.jenwald@gmail.com>
Date: Tue, 13 Jun 2017 10:22:11 +0200
Subject: [PATCH] Refactor `ObjectLoader` to use `Dict`s correctly, rather than
abusing their internal properties
The `ObjectLoader` currently takes an Object as input, despite actually working with `Dict`s internally. This means that at the (two) existing call-sites, we're passing in the "private" `Dict.map` property directly.
Doing this seems like an anti-pattern, and we could (and even should) simply provide the actual `Dict` when creating an `ObjectLoader` instance.
Accessing properties stored in the `Dict` is now done using the intended methods instead, in particular `getRaw` which (as the name suggests) doesn't do any de-referencing, thus maintaining the current functionality of the code.
The only functional change in this patch is that `ObjectLoader.load` will now ignore empty nodes, such that `ObjectLoader._walk` only needs to deal with nodes that are known to contain data. (This lets us skip, among other checks, meaningless `addChildren` function calls.)
---
src/core/annotation.js | 5 ++---
src/core/document.js | 5 ++---
src/core/obj.js | 33 ++++++++++++++++-----------------
3 files changed, 20 insertions(+), 23 deletions(-)
diff --git a/src/core/annotation.js b/src/core/annotation.js
index 6f81ae6ea..b1320287c 100644
--- a/src/core/annotation.js
+++ b/src/core/annotation.js
@@ -390,9 +390,8 @@ var Annotation = (function AnnotationClosure() {
if (!resources) {
return;
}
- var objectLoader = new ObjectLoader(resources.map,
- keys,
- resources.xref);
+ let objectLoader = new ObjectLoader(resources, keys, resources.xref);
+
return objectLoader.load().then(function() {
return resources;
});
diff --git a/src/core/document.js b/src/core/document.js
index e3ed0b97b..2aea50098 100644
--- a/src/core/document.js
+++ b/src/core/document.js
@@ -186,9 +186,8 @@ var Page = (function PageClosure() {
this.resourcesPromise = this.pdfManager.ensure(this, 'resources');
}
return this.resourcesPromise.then(() => {
- var objectLoader = new ObjectLoader(this.resources.map,
- keys,
- this.xref);
+ let objectLoader = new ObjectLoader(this.resources, keys, this.xref);
+
return objectLoader.load();
});
},
diff --git a/src/core/obj.js b/src/core/obj.js
index e6e114450..5d3b4acfa 100644
--- a/src/core/obj.js
+++ b/src/core/obj.js
@@ -1610,7 +1610,7 @@ var FileSpec = (function FileSpecClosure() {
})();
/**
- * A helper for loading missing data in object graphs. It traverses the graph
+ * A helper for loading missing data in `Dict` graphs. It traverses the graph
* depth first and queues up any objects that have missing data. Once it has
* has traversed as many objects that are available it attempts to bundle the
* missing data requests and then resume from the nodes that weren't ready.
@@ -1626,23 +1626,18 @@ let ObjectLoader = (function() {
}
function addChildren(node, nodesToVisit) {
- let value;
if (isDict(node) || isStream(node)) {
- let map;
- if (isDict(node)) {
- map = node.map;
- } else {
- map = node.dict.map;
- }
- for (let key in map) {
- value = map[key];
- if (mayHaveChildren(value)) {
- nodesToVisit.push(value);
+ let dict = isDict(node) ? node : node.dict;
+ let dictKeys = dict.getKeys();
+ for (let i = 0, ii = dictKeys.length; i < ii; i++) {
+ let rawValue = dict.getRaw(dictKeys[i]);
+ if (mayHaveChildren(rawValue)) {
+ nodesToVisit.push(rawValue);
}
}
} else if (isArray(node)) {
for (let i = 0, ii = node.length; i < ii; i++) {
- value = node[i];
+ let value = node[i];
if (mayHaveChildren(value)) {
nodesToVisit.push(value);
}
@@ -1650,8 +1645,8 @@ let ObjectLoader = (function() {
}
}
- function ObjectLoader(obj, keys, xref) {
- this.obj = obj;
+ function ObjectLoader(dict, keys, xref) {
+ this.dict = dict;
this.keys = keys;
this.xref = xref;
this.refSet = null;
@@ -1668,12 +1663,16 @@ let ObjectLoader = (function() {
return this.capability.promise;
}
- let keys = this.keys;
+ let { keys, dict, } = this;
this.refSet = new RefSet();
// Setup the initial nodes to visit.
let nodesToVisit = [];
for (let i = 0, ii = keys.length; i < ii; i++) {
- nodesToVisit.push(this.obj[keys[i]]);
+ let rawValue = dict.getRaw(keys[i]);
+ // Skip nodes that are guaranteed to be empty.
+ if (rawValue !== undefined) {
+ nodesToVisit.push(rawValue);
+ }
}
this._walk(nodesToVisit);