Fixed: [ Issue 52 ] Add content-assist for message options
https://code.google.com/p/protobuf-dt/issues/detail?id=52

com.google.eclipse.protobuf.ui/src/com/google/eclipse/protobuf/ui/contentassist/ProtobufProposalProvider.java

diff --git a/com.google.eclipse.protobuf.ui/src/com/google/eclipse/protobuf/ui/contentassist/ProtobufProposalProvider.java b/com.google.eclipse.protobuf.ui/src/com/google/eclipse/protobuf/ui/contentassist/ProtobufProposalProvider.java
index 503b345..5e85bcc 100644
--- a/com.google.eclipse.protobuf.ui/src/com/google/eclipse/protobuf/ui/contentassist/ProtobufProposalProvider.java
+++ b/com.google.eclipse.protobuf.ui/src/com/google/eclipse/protobuf/ui/contentassist/ProtobufProposalProvider.java
@@ -75,11 +75,13 @@
 
   @Override public void completeOption_Name(EObject model, Assignment assignment, ContentAssistContext context,
       ICompletionProposalAcceptor acceptor) {
-    EObject container = model.eContainer();
-    if (container instanceof Protobuf) {
+    if (model instanceof Option) {
       proposeCommonFileOptions(context, acceptor);
       return;
     }
+    if (model instanceof Message) {
+      proposeCommonMessageOptions(context, acceptor);
+    }
   }
 
   private void proposeCommonFileOptions(ContentAssistContext context, ICompletionProposalAcceptor acceptor) {
@@ -99,11 +101,24 @@
     }
   }
 
+  private void proposeCommonMessageOptions(ContentAssistContext context, ICompletionProposalAcceptor acceptor) {
+    for (Property messageOption : descriptorProvider.get().messageOptions()) {
+      String displayString = messageOption.getName();
+      String proposalText = displayString + SPACE + EQUAL + SPACE;
+      boolean isBooleanOption = properties.isBool(messageOption);
+      if (isBooleanOption)
+        proposalText = proposalText + TRUE;
+      ICompletionProposal proposal = createCompletionProposal(proposalText, displayString, context);
+      acceptor.accept(proposal);
+    }
+  }
+
   @Override public void completeOption_Value(EObject model, Assignment assignment, ContentAssistContext context,
       ICompletionProposalAcceptor acceptor) {
     Option option = (Option) model;
     Descriptor descriptor = descriptorProvider.get();
     Property fileOption = descriptor.lookupFileOption(option.getName());
+    if (fileOption == null) fileOption = descriptor.lookupMessageOption(option.getName());
     if (fileOption == null) return;
     if (descriptor.isOptimizeForOption(option)) {
       proposeAndAccept(descriptor.optimizedMode(), context, acceptor);

com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/scoping/Descriptor.java

diff --git a/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/scoping/Descriptor.java b/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/scoping/Descriptor.java
index a113563..50d770c 100644
--- a/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/scoping/Descriptor.java
+++ b/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/scoping/Descriptor.java
@@ -85,6 +85,11 @@
          .append("  optional bool py_generic_services = 18 [default=false];")
          .append("  extensions 1000 to max;")
          .append("}")
+         .append("message MessageOptions {")
+         .append("  optional bool message_set_wire_format = 1 [default=false];")
+         .append("  optional bool no_standard_descriptor_accessor = 2 [default=false];")
+         .append("  extensions 1000 to max;")
+         .append("}")
          .append("message FieldOptions {")
          .append("  optional CType ctype = 1 [default = STRING];")
          .append("  enum CType {")
@@ -102,6 +107,7 @@
   private void initContents() {
     for (Message m : getAllContentsOfType(root, Message.class)) {
       if (isFileOptionsMessage(m)) initFileOptions(m);
+      else if (isMessageOptionsMessage(m)) initMessageOptions(m);
       else if (isFieldOptionsMessage(m)) initFieldOptions(m);
     }
   }
@@ -110,6 +116,10 @@
     return "FileOptions".equals(m.getName());
   }
 
+  private boolean isMessageOptionsMessage(Message m) {
+    return "MessageOptions".equals(m.getName());
+  }
+
   private boolean isFieldOptionsMessage(Message m) {
     return "FieldOptions".equals(m.getName());
   }
@@ -131,6 +141,19 @@
     addOption(FILE, p);
   }
 
+  private void initMessageOptions(Message messageOptionsMessage) {
+    for (MessageElement e : messageOptionsMessage.getElements()) {
+      if (e instanceof Property) {
+        addMessageOption((Property) e);
+        continue;
+      }
+    }
+  }
+  
+  private void addMessageOption(Property p) {
+    addOption(MESSAGE, p);
+  }
+
   private void initFieldOptions(Message fieldOptionsMessage) {
     for (MessageElement e : fieldOptionsMessage.getElements()) {
       if (e instanceof Property) {
@@ -201,6 +224,27 @@
   }
 
   /**
+   * Returns all the message-level options available. These are the options defined in
+   * {@code google/protobuf/descriptor.proto} (more details can be found
+   * <a href=http://code.google.com/apis/protocolbuffers/docs/proto.html#options" target="_blank">here</a>.)
+   * @return all the message-level options available.
+   */
+  public Collection<Property> messageOptions() {
+    return optionsOfType(MESSAGE);
+  }
+
+  /**
+   * Looks up a message-level option per name. Message-level options are defined in 
+   * {@code google/protobuf/descriptor.proto} (more details can be found <a
+   * href=http://code.google.com/apis/protocolbuffers/docs/proto.html#options" target="_blank">here</a>.)
+   * @param name the name of the option to look for.
+   * @return the option whose name matches the given one or {@code null} if a matching option is not found.
+   */
+  public Property lookupMessageOption(String name) {
+    return lookupOption(MESSAGE, name);
+  }
+
+  /**
    * Returns all the field-level options available. These are the options defined in
    * {@code google/protobuf/descriptor.proto} (more details can be found
    * <a href=http://code.google.com/apis/protocolbuffers/docs/proto.html#options" target="_blank">here</a>.)

com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/scoping/OptionType.java

diff --git a/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/scoping/OptionType.java b/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/scoping/OptionType.java
index ab8ab3a..0eb4701 100644
--- a/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/scoping/OptionType.java
+++ b/com.google.eclipse.protobuf/src/com/google/eclipse/protobuf/scoping/OptionType.java
@@ -9,5 +9,5 @@
 package com.google.eclipse.protobuf.scoping;
 
 enum OptionType {
-  FILE, FIELD;
+  FILE, MESSAGE, FIELD;
 }
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