Rework RenameBlockGenerator

- Remove _id and _name params to the single old_block and new_block params
- Allow merging that is independent of ordering

refs idaholab#17710

framework/doc/content/source/meshgenerators/RenameBlockGenerator.md

@@ -2,55 +2,60 @@
 
 !syntax description /Mesh/RenameBlockGenerator
 
-## Overview
+## Renaming or Setting Block Names
 
-`RenameBlockGenerator` is usually used to provide meaningful names to blocks so that input files are easier to
-read.  For instance
+When using the `RenameBlockGenerator` to change block names, the result is independent of ordering.
 
-```text
-old_block_id = '1 2 3'
-new_block_name = 'wheel engine axle'
-```
-
-Then the MOOSE input file can employ `block = wheel` rather than `block = 1`.  `RenameBlockGenerator` may also
-be to provide more meaningful names to mesh blocks that are already named.  For instance
+The following will change the name for the block "meaningless" to "inside" and will set the name for block "5" to "outside":
 
-```text
-old_block_name = 'silly meaningless crazy'
-new_block_name = 'wheel engine axle'
+```
+[rename]
+  type = RenameBlockGenerator
+  input = some_mesh
+  old_block = 'meainingless 5'
+  new_block = 'inside outside'
+[]
 ```
 
-Then the MOOSE input file can employ `block = axle` rather than `block = crazy`.
+## Merging Blocks
 
-!alert warning
-`RenameBlockGenerator` may also be used to merge blocks, but care must be taken.
+When using the `RenameBlockGenerator` to merge blocks, the result is not necessarily independent of ordering.
 
-For instance
+For example, take the following:
 
 ```
-old_block_id = '1 2 3'
-new_block_id = '4 4 4'
+[merge]
+  type = RenameBlockGenerator
+  input = some_mesh
+  old_block = '0 1 2 3'
+  new_block = '0_and_1 0_and_1 2_and_3 2_and_3'
+[]
 ```
 
-Then blocks 1, 2 and 3 will be merged together into one block that may be used in the remainder of
-the input file.  However, when merging blocks problems and even inconsistencies can occur.
+The above will result in two blocks:
+
+- Block "0_and_1" with ID "0" that contains the elements from the original blocks "0" and "1".
+- Block "2_and_3" with ID "2" that contains the elements from the original blocks "2" and "3".
 
-Firstly, in the example just given, what if the blocks 1, 2 and 3 were named?  What should the name
-of the block 4 be?  The convention is that it is the name of the first old block that is given the
-block ID of 4, which is the name of the old block 1 in this case.  The user needs to be aware of this
-convention.  Similarly, if `old_block_name = 'oldA oldB'` and `new_block_name = 'new1 new1'`, then
-the block ID of new1 is the block ID of oldA.
+Take the first execution, "0" to "0_and_1". The `RenameBlockGenerator` will use the original block ID, which is "0". The second execution "1" to "0_and_1" will use the new ID associated with "0_and_1", which is "0", and merge "1" into it. The result is similar for the third and fourth executions.
 
-Secondly, in the example above, what if block 4 already existed?  An inconsistency could arise in the
-input file, because block 4 is now given the name of the old block 1.
+!alert! tip title=The use of ID is order independent
+The order dependent behavior only exists when the new block provided is a name. Take the following instead:
+
+```
+[merge]
+  type = RenameBlockGenerator
+  input = some_mesh
+  old_block = '0 1 2 3'
+  new_block = '0 0 4 4'
+[]
+```
 
-Thirdly, in this example `old_block_id = '1 2'` and `new_block_name = 'wheel wheel'`. What if another
-block, with a different ID, already had the name "wheel"?  This can lead to great confusion in the MOOSE input file.
+The result is:
 
-!alert note
-Given all these potential problems, when merging blocks it is strongly recommended to use just
-*one* `RenameBlock` that includes the names or IDs of *all* the blocks involved in the merging.
-This will make the new block IDs and new block names unequivocally obvious.
+- Block "0" that contains the elements from original blocks "0" and "1".
+- Block "4" that contains the elements from original blocks "2" and "3".
+!alert-end!
 
 !syntax parameters /Mesh/RenameBlockGenerator
 

framework/include/meshgenerators/RenameBlockGenerator.h

@@ -32,62 +32,13 @@ class RenameBlockGenerator : public MeshGenerator
 protected:
   std::unique_ptr<MeshBase> & _input;
 
-  std::vector<subdomain_id_type> _old_block_id;
-
-  std::vector<SubdomainName> _old_block_name;
-
-  std::vector<subdomain_id_type> _new_block_id;
-
-  std::vector<SubdomainName> _new_block_name;
-
-  /**
-   * Given a new_block_id, provide a block name, based
-   * on the old block names provided (or deduced from
-   * the old_block_ids provided).
-   *
-   * Eg, if
-   * old_block_name = 'block1 block2'
-   * new_block_id   = '4      5'
-   * Then
-   * newBlockName(4) = block1
-   * newBlockName(5) = block2
-   *
-   * In the case of merging blocks, the *first encountered*
-   * block's name is used.
-   * Eg, if
-   * old_block_name = 'asdf block4 block1'
-   * new_block_id   = '3    1      1'
-   * then
-   * newBlockName(1) = block4, because we look along
-   * new_block_id until we first encounter 1, and then get the corresponding name
-   * @param new_block_id the new block's ID number
-   * @return the name that will be given to that block
-   */
-  SubdomainName newBlockName(const subdomain_id_type & new_block_id);
-
-  /**
-   * Given a new_block_name, provide a block ID, based
-   * on the old block IDs provided (or deduced from
-   * the old_block_names provided).
-   *
-   * Eg, if
-   * old_block_id =   '4      5'
-   * new_block_name = 'block1 block2'
-   * Then
-   * newBlockID(block1) = 4
-   * newBlockID(block2) = 5
-   *
-   * In the case of merging blocks, the *first encountered*
-   * block's ID is used.
-   * Eg, if
-   * old_block_id =   '3    1      1'
-   * new_block_name = 'asdf block4 block4'
-   * then
-   * newBlockID(block4) = 1, because we look along
-   * new_block_name until we first encounter block4, and then get the corresponding ID
-   * @param new_block_name the new block's name
-   * @return the ID number that will be given to that block
-   */
-  SubdomainID newBlockID(const SubdomainName & new_block_name);
+private:
+  /// The old blocks
+  std::vector<SubdomainName> _old_block;
+  /// The new blocks
+  std::vector<SubdomainName> _new_block;
+  /// The name of the parameter that specifies the old blocks
+  std::string _old_block_param_name;
+  /// The name of the parameter that specifies the new blocks
+  std::string _new_block_param_name;
 };
-

framework/include/utils/MooseMeshUtils.h

@@ -36,6 +36,14 @@ getBoundaryIDs(const libMesh::MeshBase & mesh,
  */
 BoundaryID getBoundaryID(const BoundaryName & boundary_name, const MeshBase & mesh);
 
+/**
+ * Gets the subdomain ID associated with the given SubdomainName.
+ *
+ * This is needed because the SubdomainName can be either an ID or a name.
+ * If it is a name, the mesh is queried for the ID associated with said name.
+ */
+SubdomainID getSubdomainID(const SubdomainName & subdomain_name, const MeshBase & mesh);
+
 std::vector<subdomain_id_type> getSubdomainIDs(const libMesh::MeshBase & mesh,
                                                const std::vector<SubdomainName> & subdomain_name);
 }

framework/src/mesh/MooseMesh.C

@@ -1306,13 +1306,7 @@ MooseMesh::getSubdomainID(const SubdomainName & subdomain_name) const
   if (subdomain_name == "ANY_BLOCK_ID")
     mooseError("Please use getSubdomainIDs() when passing \"ANY_BLOCK_ID\"");
 
-  SubdomainID id = Moose::INVALID_BLOCK_ID;
-  std::istringstream ss(subdomain_name);
-
-  if (!(ss >> id) || !ss.eof())
-    id = getMesh().get_id_by_name(subdomain_name);
-
-  return id;
+  return MooseMeshUtils::getSubdomainID(subdomain_name, getMesh());
 }
 
 std::vector<SubdomainID>
@@ -1331,13 +1325,7 @@ MooseMesh::getSubdomainIDs(const std::vector<SubdomainName> & subdomain_name) co
       break;
     }
 
-    SubdomainID id = Moose::INVALID_BLOCK_ID;
-    std::istringstream ss(subdomain_name[i]);
-
-    if (!(ss >> id) || !ss.eof())
-      id = getMesh().get_id_by_name(subdomain_name[i]);
-
-    ids[i] = id;
+    ids[i] = MooseMeshUtils::getSubdomainID(subdomain_name[i], getMesh());
   }
 
   return ids;