Completion Part 5

Why is writing documentation so hard?

Manual.md

@@ -8,28 +8,28 @@ of Minetest.
 
 MapEditr reads and edits *map databases*, usually a file named `map.sqlite`
 within each Minetest world directory. As such, the terms "world" and "map" may
-be used interchangeably.
+be used interchangeably. Note that only SQLite format maps are currently
+supported.
 
-For most commands to work, the areas of the map to be read/modified must
+For most commands to work, the parts of the map to be read/modified must
 already be generated. This can be done by either exploring the area in-game,
 or by using Minetest's built-in `/emergeblocks` command.
 
 MapEditr supports all maps created since Minetest version 0.4.2-rc1, released
-July 2012. Any unsupported areas of the map will be skipped. Note that only
+July 2012. Any unsupported parts of the map will be skipped.
-SQLite format maps are currently supported.
 
 ## General usage
 
-`mapeditr [-h] [-y] <map> <subcommand>`
+`mapeditr [-h] [-y] <map> <SUBCOMMAND>`
 
 Arguments:
 
 - `-h, --help`: Print help information and exit.
 - `-y, --yes`: Skip the default confirmation prompt (for those who feel brave).
 - `<map>`: Path to the Minetest world/map to edit; this can be either a world
-directory or a `map.sqlite` file within a world folder. This file will be
+directory or a `map.sqlite` file. This world/map will be modified, so *always*
-modified, so *always* shut down the game/server before executing any command.
+shut down the game or server before executing any command.
-- `<subcommand>`: Command to execute. See "Commands" section below.
+- `<SUBCOMMAND>`: Command to execute. See the "Commands" section below.
 
 ### Common command arguments
 
@@ -37,11 +37,13 @@ modified, so *always* shut down the game/server before executing any command.
 area with corners at `p1` and `p2`, similarly to how WorldEdit's area selection
 works. Any two opposite corners can be used. These coordinates can be found
 using Minetest's F5 debug menu.
-- Node/item names: includes `node`, `new_node`, etc. Must be the full name,
+- Node/item names, including `node`, `new_node`, etc.: Must be the full name,
 e.g. "default:stone", not just "stone".
 
 ### Other tips
 
+Optional arguments are indicated using [square brackets].
+
 Text-like arguments can be surrounded with "quotes" if they contain spaces.
 
 Due to technical limitations, MapEditr will often leave lighting glitches. To
@@ -50,7 +52,7 @@ WorldEdit `//fixlight` command.
 
 ## Commands
 
-TODO: Unify documentation style, provide examples.
+TODO: Unify documentation style, argument ordering, provide examples.
 
 ### clone
 
@@ -61,30 +63,41 @@ Clone (copy) the contents of an area to a new location.
 Arguments:
 
 - `--p1, --p2`: Area to clone.
-- `--offset x y z`: Vector to shift the area by. For example, to copy an area
+- `--offset x y z`: Vector to shift the area's contents by. For example, to
-50 nodes downward (negative Y direction), use `--offset 0 -50 0`. Directions
+copy an area 50 nodes downward (negative Y direction), use `--offset 0 -50 0`.
-may be determined using Minetest's F5 debug menu.
+Directions may be determined using Minetest's F5 debug menu.
 
 This command copies nodes, param1, param2, and metadata. Nothing will be copied
 from or into mapblocks that are not yet generated.
 
+Examples:
+
+- Clone an area surrounding spawn 500 nodes west and 360 nodes north:
+`clone --p1 200 80 200 --p2 -200 -15 -200 --offset -500 0 360`
+
 ### deleteblocks
 
 Usage: `deleteblocks --p1 x y z --p2 x y z [--invert]`
 
-Delete all mapblocks inside or outside an area.
+Delete all mapblocks inside or outside an area. This command is often much
+faster than Minetest's built-in `/deleteblocks` command.
 
 Arguments:
 
 - `--p1, --p2`: Area containing mapblocks to delete. By default, only mapblocks
 fully within this area will be deleted.
-- `--invert`: If present, delete all mapblocks fully *outside* the given area.
+- `--invert`: Delete all mapblocks fully *outside* the given area. Use with
-Use with caution; you could erase a large portion of your world!
+caution; you could erase a large portion of your world!
 
 **Note:** Deleting mapblocks is *not* the same as filling them with air! Mapgen
 will be invoked where the blocks were deleted, and this sometimes causes
 terrain glitches.
 
+Examples:
+
+- Delete all saved mapblocks below y = -200 and above y = 200:
+`deleteblocks --p1 -31000 -200 -31000 --p2 31000 200 31000 --invert`
+
 ### deletemeta
 
 Usage: `deletemeta [--node <node>] [--p1 x y z] [--p2 x y z] [--invert]`
@@ -98,7 +111,7 @@ Arguments:
 specified, metadata will be deleted from any node.
 - `--p1, --p2`: (Optional) Area in which to delete metadata. If not specified,
 metadata will be deleted everywhere.
-- `--invert`: If present, delete metadata *outside* the given area.
+- `--invert`: Delete metadata *outside* the given area.
 
 ### deleteobjects
 
@@ -109,15 +122,22 @@ Delete certain objects (entities) and/or item entities (dropped items).
 Arguments:
 
 - `--obj <object>`: (Optional) Name of object to delete, e.g. "boats:boat".
-- `--items [items]`: If present, delete only item entities (dropped items). If
+- `--items [items]`: (Optional) Delete only item entities (dropped items). If
 one or more item names are listed after `--items`, only those items will be
 deleted.
 - `--p1, --p2`: (Optional) Area in which to delete objects. If not specified,
 objects will be deleted everywhere.
-- `--invert`: If present, delete objects *outside* the given area.
+- `--invert`: Delete objects *outside* the given area.
 
 `--obj` and `--items` cannot be used simultaneously.
 
+Examples:
+
+- Delete all objects: `deleteobjects`
+- Delete all cart entities: `deleteobjects --obj carts:cart`
+- Delete dropped stone and gravel:
+`deleteobjects --items default:stone default:gravel`
+
 ### deletetimers
 
 Usage: `deletetimers [--node <node>] [--p1 x y z] [--p2 x y z] [--invert]`
@@ -126,17 +146,18 @@ Delete node timers of certain nodes.
 
 Arguments:
 
-- `--node <node>`: If specified, only delete node timers from nodes with the
+- `--node <node>`: (Optional) Name of node to delete node timers from. If not
-given name.
+specified, node timers of any node will be deleted.
-- `--p1, --p2`: (Optional) Area in which to delete node timers.
+- `--p1, --p2`: (Optional) Area in which to delete node timers. If not
+specified, node timers will be deleted everywhere.
 - `--invert`: Delete node timers *outside* the given area.
 
 ### fill
 
 Usage: `fill --p1 x y z --p2 x y z [--invert] <new_node>`
 
-Fills everything inside or outside an area with one node. Mapblocks that are
+Set all nodes inside or outside an area. Mapblocks that are not yet generated
-not yet generated will not be affected.
+will not be affected.
 
 This command does not affect param2, node metadata, etc.
 
@@ -144,7 +165,14 @@ Arguments:
 
 - `--p1, --p2`: Area to fill.
 - `--invert`: Fill all generated nodes *outside* the given area.
-- `<new_node>`: Name of node to fill the area with.
+- `<new_node>`: Name of the node to fill with.
+
+Examples:
+
+- Carve out a large hole in the ground:
+`fill --p1 224 50 347 --p2 817 -40 73 air`
+- Build a long obsidian glass wall travelling north/south:
+`fill --p1 0 -30 -10000 --p2 0 30 10000 default:obsidian_glass`
 
 ### overlay
 
@@ -154,52 +182,63 @@ Copy part or all of a source map into the main map.
 
 Arguments:
 
-- `<input_map>`: Path to the source map/world. This world will not be modified.
+- `<input_map>`: Path to the source map/world. This map will not be modified.
-- `--p1, --p2`: Area to copy from. If not specified, MapEditr will try to
+- `--p1, --p2`: (Optional) Area to copy from. If not specified, MapEditr will
-copy everything from the source map.
+try to copy everything from the source map.
-- `--invert`: If present, copy everything *outside* the given area.
+- `--invert`: Copy everything *outside* the given area.
-- `--offset x y z`: Vector to shift nodes by when copying; default is no
+- `--offset x y z`: (Optional) Vector to shift nodes by when copying; default
-offset. Currently, an offset cannot be used with an inverted selection.
+is no offset. Currently, an offset cannot be used with an inverted selection.
+
+**If an area and/or offset is used:** To ensure that all data is copied, make
+sure at least the "edges" of the destination area are generated, or the entire
+destination area if using an offset.
 
 This command will always copy nodes, param1, param2, and metadata. If no
 offset is used, objects/entities and node timers may also be copied.
 
-To ensure that all data is copied, make sure the edges of the selection are
+**Tip:** Overlay will be significantly faster if no offset is used.
-generated in the destination map, or the entire selection if an offset is used.
 
-**Tip:** Overlay will be significantly faster if no offset is used, as
+Examples (your world/map paths will vary):
-mapblocks can be copied verbatim.
+
+- Copy all of map `backup.sqlite` into the main world:
+`overlay backup-maps/backup.sqlite`
+- Copy world `test` into the main world, excluding the area within 120 nodes of
+spawn: `overlay test --p1 -120 -120 -120 --p2 120 120 120 --invert`
+- Copy an area from `map.sqlite` into the main world, moving it 32 nodes north:
+`overlay map.sqlite --p1 6 36 -49 --p2 -9 74 -78 --offset 0 0 32`
 
 ### replaceininv
 
-Usage: `replaceininv [--delete] [--deletemeta] [--nodes <nodes>] [--p1 x y z] [--p2 x y z] [--invert] <item> [new_item]`
+Usage: `replaceininv <item> [new_item] [--delete] [--deletemeta] [--nodes <nodes>] [--p1 x y z] [--p2 x y z] [--invert]`
 
 Replace, delete, or modify items in certain node inventories.
 
 Arguments:
 
-- `<item>`: Name of the item to replace/delete
+- `<item>`: Name of the item to replace/delete.
-- `[new_item]`: Name of the new item, if replacing items.
+- `[new_item]`: (Optional) Name of the new item, if replacing items.
 - `--delete`: Delete items instead of replacing them.
 - `--deletemeta`: Delete metadata of affected items. May be used with or
 without `new_item`, depending on whether items should also be replaced.
-- `--nodes <nodes>`: Names of one or more nodes to modify inventories of. If
+- `--nodes <nodes>`: (Optional) Names of one or more nodes to modify
-not specified, items will be modified in any node with an inventory.
+inventories of. If not specified, items will be modified in any node with an
-- `--p1, --p2`: Area in which to modify node inventories. If not specified,
+inventory.
-items will be modified everywhere.
+- `--p1, --p2`: (Optional) Area in which to modify node inventories. If not
+specified, items will be modified everywhere.
 - `--invert`: Modify node inventories *outside* the given area.
 
 Examples:
 
-Replace all written books in chests with unwritten books, deleting metadata:
+- Delete all lava buckets:
-
+`replaceininv bucket:bucket_lava --delete`
+- Replace all written books in chests with unwritten books, deleting metadata:
 `replaceininv default:book_written default:book --deletemeta --nodes default:chest default:chest_locked`
 
 ### replacenodes
 
-Usage: `replacenodes [--p1 x y z] [--p2 x y z] [--invert] <node> <new_node>`
+Usage: `replacenodes <node> <new_node> [--p1 x y z] [--p2 x y z] [--invert]`
 
-Replace all of one node with another node. Can be used to remove unknown nodes
+Replace one node with another node. Can also be used to remove unknown nodes
 or swap a node that changed names.
 
 This command does not affect param2, metadata, etc.
@@ -208,28 +247,43 @@ Arguments:
 
 - `<node>`: Name of node to replace.
 - `<new_node>`: Name of node to replace with.
-- `--p1, --p2`: Area in which to replace nodes. If not specified, nodes will be
+- `--p1, --p2`: (Optional) Area in which to replace nodes. If not specified,
-replaced across the entire map.
+nodes will be replaced across the entire map.
 - `--invert`: Replace nodes *outside* the given area.
 
+Examples:
+
+- Replace all legacy PB&J pup nodes with mese blocks:
+`replacenodes pbj_pup:pbj_pup default:mese`
+- Remove fire nodes near ground level:
+`replacenodes fire:basic_flame air --p1 -31000 -80 -31000 --p2 31000 200 31000`
+
 ### setmetavar
 
-Usage: `setmetavar [--node <node>] [--p1 x y z] [--p2 x y z] [--invert] <key> <value>`
+Usage: `setmetavar <key> [value] [--delete] [--nodes <nodes>] [--p1 x y z] [--p2 x y z] [--invert]`
 
-Set or delete a variable in node metadata of certain nodes. This only works on metadata
+Set or delete a variable in node metadata of certain nodes. This only works on
-where the variable is already set.
+nodes where the variable is already set.
 
 Arguments:
 
 - `<key>`: Name of variable to set/delete, e.g. `infotext`, `formspec`, etc.
-- `<value>`: Value to set variable to, if setting a value. This should be a
+- `[value]`: Value to set variable to, if setting a value. This should be a
 string.
 - `--delete`: Delete the variable.
-- `--nodes <nodes>`: Names of one or more nodes to modify. If not specified,
+- `--nodes <nodes>`: (Optional) Names of one or more nodes to modify. If not
-any node with the given variable will be modified.
+specified, any node with the given variable will be modified.
-- `--p1, --p2`: Area in which to modify node metadata.
+- `--p1, --p2`: (Optional) Area in which to modify node metadata. If not
+specified, nodes will be modified everywhere.
 - `--invert`: Modify node metadata *outside* the given area.
 
+Examples:
+
+- Clear infotext of signs:
+`setmetavar infotext --delete --nodes default:sign_wall_steel default:sign_wall_wood`
+- Set "player1" as the owner of all steel trapdoors:
+`setmetavar owner player1 --nodes doors:trapdoor_steel`
+
 ### setparam2
 
 Usage: `setparam2 [--node <node>] [--p1 x y z] [--p2 x y z] [--invert] <param2>`
@@ -238,25 +292,26 @@ Set param2 values of certain nodes.
 
 Arguments:
 
-- `<param2>`: New param2 value, between 0 and 255.
+- `--node <node>`: (Optional) Name of node to modify. If not specified, the
-- `--node <node>`: Name of node to modify. If not specified, the param2 values
+param2 values of any node will be set.
-of any node will be set.
+- `--p1, --p2`: (Optional) Area in which to set param2 values. If not
-- `--p1, --p2`: Area in which to set param2 values.
+specified, param2 will be set everywhere.
 - `--invert`: Set param2 values *outside* the given area.
+- `<param2>`: New param2 value, between 0 and 255.
 
-An area and/or node is required for setparam2.
+An area and/or node is required for this command.
 
 ### vacuum
 
 Usage: `vacuum`
 
-Vacuums the database. This reduces the size of the database, but may take a
+Rebuild the map database to reduce its size. Vacuuming may take a long time for
-long time.
+large maps.
 
-All this does is perform an SQLite `VACUUM` command. This shrinks and optimizes
+This command simply executes the SQLite `VACUUM` command, which shrinks and
-the database by efficiently "repacking" all mapblocks. No map data is changed
+optimizes the map database by efficiently "repacking" all mapblocks. No map
-or deleted.
+data is changed or deleted.
 
-**Note:** Because data is copied into another file, vacuum could require
+**Note:** Because data is temporarily copied into another file, vacuum could
-as much free disk space as is already occupied by the map. For example, if
+require as much free disk space as is already occupied by the map. For example,
-map.sqlite is 10 GB, make sure you have **at least 10 GB** of free space!
+if map.sqlite is 10 GB, make sure you have **at least 10 GB** of free space!

README.md

@@ -36,10 +36,11 @@ runs much faster than the default, unoptimized version.
 For an overview of how MapEditr works and a listing of commands and their
 usages, see [Manual.md](Manual.md).
 
-Some useful things you can do with MapEditr:
+These are just a few of the useful things you can do with MapEditr:
 
 - Remove unknown nodes left by old mods with `replacenodes`.
 - Build extremely long walls and roads in seconds using `fill`.
+- Selectively delete entities and/or dropped items using `deleteobjects`.
 - Combine multiple worlds or map saves with `overlay`.
 
 ## License

src/cmd_line.rs

@@ -316,7 +316,7 @@ pub fn run_cmd_line() {
 				},
 				ServerEvent::ConfirmRequest => {
 					newline_if(&mut need_newline);
-					status.confirm(get_confirmation());
+					status.send_confirmation(get_confirmation());
 				},
 			},
 			Err(err) => {

src/commands/clone.rs

@@ -128,7 +128,7 @@ pub fn get_command() -> Command {
 		verify_args: Some(verify_args),
 		args: vec![
 			(ArgType::Area(true), "Area to clone"),
-			(ArgType::Offset(true), "Vector to shift the area by")
+			(ArgType::Offset(true), "Vector to shift the area's contents by")
 		],
 		help: "Clone (copy) the contents of an area to a new location."
 	}

src/commands/delete_blocks.rs

@@ -25,8 +25,7 @@ pub fn get_command() -> Command {
 		args: vec![
 			(ArgType::Area(true), "Area containing mapblocks to delete"),
 			(ArgType::Invert,
-				"If present, delete all mapblocks fully *outside* the given \
+				"Delete all mapblocks fully *outside* the given area.")
-				area.")
 		],
 		help: "Delete all mapblocks inside or outside an area."
 	}

src/commands/delete_meta.rs

@@ -83,10 +83,9 @@ pub fn get_command() -> Command {
 		func: delete_metadata,
 		verify_args: Some(verify_args),
 		args: vec![
+			(ArgType::Node(false), "Name of node to delete metadata from"),
 			(ArgType::Area(false), "Area in which to delete metadata"),
-			(ArgType::Invert,
+			(ArgType::Invert, "Delete metadata *outside* the given area."),
-				"If present, delete metadata *outside* the given area."),
-			(ArgType::Node(false), "Name of node to delete metadata from")
 		],
 		help: "Delete node metadata of certain nodes."
 	}

src/commands/delete_objects.rs

@@ -132,13 +132,12 @@ pub fn get_command() -> Command {
 		func: delete_objects,
 		verify_args: Some(verify_args),
 		args: vec![
-			(ArgType::Area(false), "Area in which to delete objects"),
-			(ArgType::Invert,
-					"If present, delete objects *outside* the given area."),
 			(ArgType::Object, "Name of object to delete"),
 			(ArgType::Items,
-				"If present, delete item entities. Optionally list one or \
+				"Delete only item entities. Optionally list one or more item \
-				more item names after `--items` to delete only those items."),
+				names after `--items` to delete only those items."),
+			(ArgType::Area(false), "Area in which to delete objects"),
+			(ArgType::Invert, "Delete objects *outside* the given area."),
 		],
 		help: "Delete certain objects and/or item entities."
 	}

src/commands/delete_timers.rs

@@ -68,11 +68,9 @@ pub fn get_command() -> Command {
 		func: delete_timers,
 		verify_args: None,
 		args: vec![
-			(ArgType::Area(false), "Area in which to delete timers"),
+			(ArgType::Node(false), "Name of node to delete node timers from"),
+			(ArgType::Area(false), "Area in which to delete node timers"),
 			(ArgType::Invert, "Delete node timers *outside* the given area."),
-			(ArgType::Node(false),
-				"Node to delete timers from. If not specified, node timers \
-				will be deleted from any node.")
 		],
 		help: "Delete node timers of certain nodes."
 	}

src/commands/fill.rs

@@ -82,8 +82,8 @@ pub fn get_command() -> Command {
 			(ArgType::Area(true), "Area to fill"),
 			(ArgType::Invert,
 				"Fill all generated nodes *outside* the given area."),
-			(ArgType::NewNode, "Name of node to fill the area with"),
+			(ArgType::NewNode, "Name of the node to fill with"),
 		],
-		help: "Fill the entire area with one node."
+		help: "Set all nodes inside or outside an area."
 	}
 }

src/commands/overlay.rs

@@ -228,8 +228,7 @@ pub fn get_command() -> Command {
 			(ArgType::InputMapPath, "Path to the source map/world"),
 			(ArgType::Area(false), "Area to copy from. If not specified, \
 				everything from the source map will be copied."),
-			(ArgType::Invert,
+			(ArgType::Invert, "Copy everything *outside* the given area."),
-				"If present, copy everything *outside* the given area."),
 			(ArgType::Offset(false), "Vector to shift nodes by when copying"),
 		],
 		help: "Copy part or all of a source map into the main map."

src/commands/replace_nodes.rs

@@ -146,6 +146,6 @@ pub fn get_command() -> Command {
 			(ArgType::Area(false), "Area in which to replace nodes"),
 			(ArgType::Invert, "Replace nodes *outside* the given area.")
 		],
-		help: "Replace all of one node with another node."
+		help: "Replace one node with another node."
 	}
 }

src/commands/set_param2.rs

@@ -60,8 +60,6 @@ fn set_param2(inst: &mut InstBundle) {
 	inst.status.begin_editing();
 
 	let mut count: u64 = 0;
-	use crate::time_keeper::TimeKeeper;
-	let mut tk = TimeKeeper::new();
 	for key in keys {
 		inst.status.inc_done();
 
@@ -81,7 +79,6 @@ fn set_param2(inst: &mut InstBundle) {
 			.filter(|a| a.contains_block(pos) != a.touches_block(pos))
 		{ // Modify part of block
 			let block_part = area.rel_block_overlap(pos).unwrap();
-			let _t = tk.get_timer("set_param2_partial");
 			count += set_param2_partial(&mut block,
 				block_part, inst.args.invert, node_id, param2_val);
 		} else { // Modify whole block
@@ -102,7 +99,6 @@ fn set_param2(inst: &mut InstBundle) {
 	}
 
 	inst.status.end_editing();
-	tk.print(&mut inst.status);
 	inst.status.log_info(format!("Set param2 of {} nodes.",
 		fmt_big_num(count)));
 }
@@ -122,10 +118,10 @@ pub fn get_command() -> Command {
 		func: set_param2,
 		verify_args: Some(verify_args),
 		args: vec![
-			(ArgType::Param2, "New param2 value, between 0 and 255"),
+			(ArgType::Node(false), "Name of node to modify"),
-			(ArgType::Node(false), "Node to set param2 values of"),
 			(ArgType::Area(false), "Area in which to set param2 values"),
 			(ArgType::Invert, "Set param2 values *outside* the given area."),
+			(ArgType::Param2, "New param2 value, between 0 and 255"),
 		],
 		help: "Set param2 values of certain nodes."
 	}

src/commands/vacuum.rs

@@ -13,7 +13,7 @@ fn vacuum(inst: &mut InstBundle) {
 
 	match res {
 		Ok(_) => {
-			inst.status.log_info(format!("Completed vacuum."));
+			inst.status.log_info("Completed vacuum.");
 		},
 		Err(e) => inst.status.log_error(format!("Vacuum failed: {}.", e))
 	}

src/instance.rs

@@ -8,6 +8,7 @@ use crate::spatial::{Vec3, Area, MAP_LIMIT};
 use crate::map_database::MapDatabase;
 use crate::commands;
 use crate::commands::ArgResult;
+use crate::utils::fmt_big_num;
 
 
 #[derive(Clone)]
@@ -200,7 +201,7 @@ impl StatusClient {
 		&self.event_rx
 	}
 
-	pub fn confirm(&self, choice: bool) {
+	pub fn send_confirmation(&self, choice: bool) {
 		self.event_tx.send(ClientEvent::ConfirmResponse(choice)).unwrap();
 	}
 }
@@ -235,8 +236,6 @@ pub struct InstBundle<'a> {
 
 
 fn verify_args(args: &InstArgs) -> anyhow::Result<()> {
-	// TODO: Complete verifications.
-
 	if args.area.is_none() && args.invert {
 		anyhow::bail!("Cannot invert without a specified area.");
 	}
@@ -314,7 +313,7 @@ fn open_map(path: PathBuf, flags: sqlite::OpenFlags)
 		if with_file.is_file() {
 			with_file
 		} else {
-			anyhow::bail!("could not find map file");
+			anyhow::bail!("Could not find the map file.");
 		}
 	};
 
@@ -335,17 +334,20 @@ fn compute_thread(args: InstArgs, status: StatusServer) -> anyhow::Result<()> {
 		}
 	}
 
-	let db_conn = open_map(PathBuf::from(&args.map_path),
+	let db_conn = open_map(
-		sqlite::OpenFlags::new().set_read_write())?;
+		PathBuf::from(&args.map_path),
+		sqlite::OpenFlags::new().set_read_write()
+	).context("Failed to open main world/map.")?;
 	let db = MapDatabase::new(&db_conn)
-		.context("Failed to open main world/map.")?;
+		.context("Main world or map database is invalid.")?;
 
-	let idb_conn = args.input_map_path.as_deref().map(
+	let idb_conn = args.input_map_path.as_deref()
-		|imp| open_map(PathBuf::from(imp),
+		.map(|imp| open_map(PathBuf::from(imp),
-			sqlite::OpenFlags::new().set_read_only())
+			sqlite::OpenFlags::new().set_read_only()))
-	).transpose().context("Failed to open input world/map.")?;
+		.transpose().context("Failed to open input world/map.")?;
 	let idb = match &idb_conn {
-		Some(conn) => Some(MapDatabase::new(conn)?),
+		Some(conn) => Some(MapDatabase::new(conn)
+			.context("Input world or map database is invalid.")?),
 		None => None
 	};
 
@@ -370,7 +372,9 @@ fn compute_thread(args: InstArgs, status: StatusServer) -> anyhow::Result<()> {
 	let fails = inst.status.get_status().blocks_failed;
 	if fails > 0 {
 		inst.status.log_info(format!(
-			"Skipped {} invalid/unsupported mapblocks.", fails));
+			"Skipped {} invalid/unsupported mapblocks.",
+			fmt_big_num(fails as u64)
+		));
 	}
 
 	if inst.db.is_in_transaction() {

src/main.rs

@@ -1,4 +1,5 @@
-mod time_keeper;
+// Kept for testing purposes
+// mod time_keeper;
 mod spatial;
 mod utils;
 mod map_database;
@@ -9,8 +10,7 @@ mod commands;
 mod cmd_line;
 
 
-// TODO: Check for unnecessary #derives!
 fn main() {
-	// TODO: Add GUI. hmm...
+	// TODO: Add a GUI. hmm...
 	cmd_line::run_cmd_line();
 }

src/map_block/compression.rs

@@ -34,6 +34,10 @@ impl Compress for Vec<u8> {
 }
 
 
+/// Stores some data and its zlib-compressed equivalent.
+///
+/// The goal of this struct is to avoid recompressing data that was not
+/// modified from its original compressed form.
 #[derive(Clone, Debug)]
 pub struct ZlibContainer<T: Compress> {
 	compressed: Option<Vec<u8>>,

src/map_block/map_block.rs

@@ -12,7 +12,7 @@ pub fn is_valid_generated(data: &[u8]) -> bool {
 }
 
 
-#[derive(Debug, Clone)]
+#[derive(Clone, Debug)]
 pub struct MapBlock {
 	pub version: u8,
 	pub flags: u8,

src/map_block/metadata.rs

@@ -9,7 +9,7 @@ use memmem::{Searcher, TwoWaySearcher};
 const END_STR: &[u8; 13] = b"EndInventory\n";
 
 
-#[derive(Debug, Clone)]
+#[derive(Clone, Debug)]
 pub struct NodeMetadata {
 	pub vars: HashMap<Vec<u8>, (Vec<u8>, bool)>,
 	pub inv: Vec<u8>
@@ -100,20 +100,21 @@ impl NodeMetadataListExt for NodeMetadataList {
 	fn serialize(&self, block_version: u8) -> Vec<u8> {
 		let buf = Vec::new();
 		let mut data = Cursor::new(buf);
+		// Skip empty metadata when serializing.
+		let count = self.iter().filter(|&(_, m)| !m.is_empty()).count();
 
-		if self.len() == 0 {
+		if count == 0 {
 			data.write_u8(0).unwrap();
 		} else {
 			let version = if block_version >= 28 { 2 } else { 1 };
 			data.write_u8(version).unwrap();
-			data.write_u16::<BigEndian>(self.len() as u16).unwrap();
+			data.write_u16::<BigEndian>(count as u16).unwrap();
 
 			for (&pos, meta) in self {
-				if meta.is_empty() {
+				if !meta.is_empty() {
-					continue; // Skip empty metadata.
+					data.write_u16::<BigEndian>(pos).unwrap();
+					meta.serialize(&mut data, version);
 				}
-				data.write_u16::<BigEndian>(pos).unwrap();
-				meta.serialize(&mut data, version);
 			}
 		}
 

src/map_block/name_id_map.rs

@@ -5,7 +5,7 @@ use std::collections::BTreeMap;
 /// Maps 16-bit node IDs to actual node names.
 ///
 /// Relevant Minetest source file: /src/nameidmapping.cpp
-#[derive(Debug, Clone)]
+#[derive(Clone, Debug)]
 pub struct NameIdMap(pub BTreeMap<u16, Vec<u8>>);
 
 impl NameIdMap {

src/map_block/node_timer.rs

@@ -2,7 +2,7 @@ use super::*;
 use std::cmp::min;
 
 
-#[derive(Debug, Clone)]
+#[derive(Clone, Debug)]
 pub struct NodeTimer {
 	pub pos: u16,
 	pub timeout: u32,