X-Git-Url: http://nitlanguage.org

diff --git a/src/loader.nit b/src/loader.nit
index 5d20c9c..f5b7be1 100644
--- a/src/loader.nit
+++ b/src/loader.nit
@@ -18,6 +18,7 @@
 module loader
 
 import modelbuilder_base
+import ini
 
 redef class ToolContext
 	# Option --path
@@ -96,7 +97,7 @@ redef class ModelBuilder
 	fun parse_group(mgroup: MGroup): Array[MModule]
 	do
 		var res = new Array[MModule]
-		visit_group(mgroup)
+		scan_group(mgroup)
 		for mg in mgroup.in_nesting.smallers do
 			for mp in mg.module_paths do
 				var nmodule = self.load_module(mp.filepath)
@@ -115,14 +116,14 @@ redef class ModelBuilder
 	#
 	# Each name can be:
 	#
-	# * a path to a module, a group or a directory of projects.
+	# * a path to a module, a group or a directory of packages.
 	# * a short name of a module or a group that are looked in the `paths` (-I)
 	#
 	# Then, for each entry, if it is:
 	#
 	# * a module, then is it parser and returned.
 	# * a group then recursively all its modules are parsed.
-	# * a directory of projects then all the modules of all projects are parsed.
+	# * a directory of packages then all the modules of all packages are parsed.
 	# * else an error is displayed.
 	#
 	# See `parse` for details.
@@ -203,45 +204,21 @@ redef class ModelBuilder
 	do
 		# First, look in groups
 		var c = mgroup
-		while c != null do
-			var dirname = c.filepath
-			if dirname == null then break # virtual group
-			if dirname.has_suffix(".nit") then break # singleton project
-
-			# Second, try the directory to find a file
-			var try_file = dirname + "/" + name + ".nit"
-			if try_file.file_exists then
-				var res = self.identify_file(try_file.simplify_path)
-				assert res != null
-				return res
-			end
-
-			# Third, try if the requested module is itself a group
-			try_file = dirname + "/" + name + "/" + name + ".nit"
-			if try_file.file_exists then
-				var res = self.identify_file(try_file.simplify_path)
-				assert res != null
-				return res
-			end
-
-			# Fourth, try if the requested module is itself a group with a src
-			try_file = dirname + "/" + name + "/src/" + name + ".nit"
-			if try_file.file_exists then
-				var res = self.identify_file(try_file.simplify_path)
-				assert res != null
-				return res
-			end
-
-			c = c.parent
+		if c != null then
+			var r = c.mpackage.root
+			assert r != null
+			scan_group(r)
+			var res = r.mmodule_paths_by_name(name)
+			if res.not_empty then return res.first
 		end
 
 		# Look at some known directories
 		var lookpaths = self.paths
 
-		# Look in the directory of the group project also (even if not explicitly in the path)
+		# Look in the directory of the group package also (even if not explicitly in the path)
 		if mgroup != null then
 			# path of the root group
-			var dirname = mgroup.mproject.root.filepath
+			var dirname = mgroup.mpackage.root.filepath
 			if dirname != null then
 				dirname = dirname.join_path("..").simplify_path
 				if not lookpaths.has(dirname) and dirname.file_exists then
@@ -272,6 +249,14 @@ redef class ModelBuilder
 	do
 		var path = search_mmodule_by_name(anode, mgroup, name)
 		if path == null then return null # Forward error
+		return load_module_path(path)
+	end
+
+	# Load and process importation of a given ModulePath.
+	#
+	# Basically chains `load_module` and `build_module_importation`.
+	fun load_module_path(path: ModulePath): nullable MModule
+	do
 		var res = self.load_module(path.filepath)
 		if res == null then return null # Forward error
 		# Load imported module
@@ -283,50 +268,37 @@ redef class ModelBuilder
 	# If found, the path of the file is returned
 	private fun search_module_in_paths(location: nullable Location, name: String, lookpaths: Collection[String]): nullable ModulePath
 	do
-		var candidate: nullable String = null
+		var res = new ArraySet[ModulePath]
 		for dirname in lookpaths do
-			var try_file = (dirname + "/" + name + ".nit").simplify_path
-			if try_file.file_exists then
-				if candidate == null then
-					candidate = try_file
-				else if candidate != try_file then
-					# try to disambiguate conflicting modules
-					var abs_candidate = module_absolute_path(candidate)
-					var abs_try_file = module_absolute_path(try_file)
-					if abs_candidate != abs_try_file then
-						toolcontext.error(location, "Error: conflicting module file for `{name}`: `{candidate}` `{try_file}`")
-					end
-				end
+			# Try a single module file
+			var mp = identify_file((dirname/"{name}.nit").simplify_path)
+			if mp != null then res.add mp
+			# Try the default module of a group
+			var g = get_mgroup((dirname/name).simplify_path)
+			if g != null then
+				scan_group(g)
+				res.add_all g.mmodule_paths_by_name(name)
 			end
-			try_file = (dirname + "/" + name + "/" + name + ".nit").simplify_path
-			if try_file.file_exists then
-				if candidate == null then
-					candidate = try_file
-				else if candidate != try_file then
-					# try to disambiguate conflicting modules
-					var abs_candidate = module_absolute_path(candidate)
-					var abs_try_file = module_absolute_path(try_file)
-					if abs_candidate != abs_try_file then
-						toolcontext.error(location, "Error: conflicting module file for `{name}`: `{candidate}` `{try_file}`")
-					end
-				end
-			end
-			try_file = (dirname + "/" + name + "/src/" + name + ".nit").simplify_path
-			if try_file.file_exists then
-				if candidate == null then
-					candidate = try_file
-				else if candidate != try_file then
-					# try to disambiguate conflicting modules
-					var abs_candidate = module_absolute_path(candidate)
-					var abs_try_file = module_absolute_path(try_file)
-					if abs_candidate != abs_try_file then
-						toolcontext.error(location, "Error: conflicting module file for `{name}`: `{candidate}` `{try_file}`")
-					end
-				end
+		end
+		if res.is_empty then return null
+		if res.length > 1 then
+			toolcontext.error(location, "Error: conflicting module files for `{name}`: `{res.join(",")}`")
+		end
+		return res.first
+	end
+
+	# Search groups named `name` from paths `lookpaths`.
+	private fun search_group_in_paths(name: String, lookpaths: Collection[String]): ArraySet[MGroup]
+	do
+		var res = new ArraySet[MGroup]
+		for dirname in lookpaths do
+			# try a single group directory
+			var mg = get_mgroup(dirname/name)
+			if mg != null then
+				res.add mg
 			end
 		end
-		if candidate == null then return null
-		return identify_file(candidate)
+		return res
 	end
 
 	# Cache for `identify_file` by realpath
@@ -336,16 +308,24 @@ redef class ModelBuilder
 	# See `identify_file`.
 	var identified_files = new Array[ModulePath]
 
-	# Identify a source file
-	# Load the associated project and groups if required
+	# Identify a source file and load the associated package and groups if required.
 	#
-	# Silently return `null` if `path` is not a valid module path.
+	# This method does what the user expects when giving an argument to a Nit tool.
+	#
+	# * If `path` is an existing Nit source file (with the `.nit` extension),
+	#   then the associated ModulePath is returned
+	# * If `path` is a directory (with a `/`),
+	#   then the ModulePath of its default module is returned (if any)
+	# * If `path` is a simple identifier (eg. `digraph`),
+	#   then the main module of the package `digraph` is searched in `paths` and returned.
+	#
+	# Silently return `null` if `path` does not exists or cannot be identified.
 	fun identify_file(path: String): nullable ModulePath
 	do
 		# special case for not a nit file
 		if path.file_extension != "nit" then
 			# search dirless files in known -I paths
-			if path.dirname == "" then
+			if not path.chars.has('/') then
 				var res = search_module_in_paths(null, path, self.paths)
 				if res != null then return res
 			end
@@ -366,6 +346,11 @@ redef class ModelBuilder
 			path = candidate
 		end
 
+		# Does the file exists?
+		if not path.file_exists then
+			return null
+		end
+
 		# Fast track, the path is already known
 		var pn = path.basename(".nit")
 		var rp = module_absolute_path(path)
@@ -376,12 +361,19 @@ redef class ModelBuilder
 		var mgroup = get_mgroup(mgrouppath)
 
 		if mgroup == null then
-			# singleton project
-			var mproject = new MProject(pn, model)
-			mgroup = new MGroup(pn, mproject, null) # same name for the root group
+			# singleton package
+			var mpackage = new MPackage(pn, model)
+			mgroup = new MGroup(pn, mpackage, null) # same name for the root group
 			mgroup.filepath = path
-			mproject.root = mgroup
-			toolcontext.info("found project `{pn}` at {path}", 2)
+			mpackage.root = mgroup
+			toolcontext.info("found singleton package `{pn}` at {path}", 2)
+
+			# Attach homonymous `ini` file to the package
+			var inipath = path.dirname / "{pn}.ini"
+			if inipath.file_exists then
+				var ini = new ConfigTree(inipath)
+				mpackage.ini = ini
+			end
 		end
 
 		var res = new ModulePath(pn, path, mgroup)
@@ -417,53 +409,72 @@ redef class ModelBuilder
 			return mgroups[rdp]
 		end
 
-		# Hack, a group is determined by one of the following:
-		# * the presence of a honomymous nit file
-		# * the fact that the directory is named `src`
-		# * the fact that there is a sub-directory named `src`
+		# Filter out non-directories
+		var stat = dirpath.file_stat
+		if stat == null or not stat.is_dir then
+			mgroups[rdp] = null
+			return null
+		end
+
+		# By default, the name of the package or group is the base_name of the directory
 		var pn = rdp.basename(".nit")
-		var mp = dirpath.join_path(pn + ".nit").simplify_path
-
-		# dirpath2 is the root directory
-		# dirpath is the src subdirectory directory, if any, else it is the same that dirpath2
-		var dirpath2 = dirpath
-		if not mp.file_exists then
-			if pn == "src" then
-				# With a src directory, the group name is the name of the parent directory
-				dirpath2 = rdp.dirname
-				pn = dirpath2.basename("")
-			else
-				# Check a `src` subdirectory
-				dirpath = dirpath2 / "src"
-				if not dirpath.file_exists then
-					# All rules failed, so return null
+
+		# Check `package.ini` that indicate a package
+		var ini = null
+		var parent = null
+		var inipath = dirpath / "package.ini"
+		if inipath.file_exists then
+			ini = new ConfigTree(inipath)
+		end
+
+		if ini == null then
+			# No ini, multiple course of action
+
+			# The root of the directory hierarchy in the file system.
+			if rdp == "/" then
+				mgroups[rdp] = null
+				return null
+			end
+
+			# Special stopper `packages.ini`
+			if (dirpath/"packages.ini").file_exists then
+				# dirpath cannot be a package since it is a package directory
+				mgroups[rdp] = null
+				return null
+			end
+
+			# check the parent directory (if it does not contain the stopper file)
+			var parentpath = dirpath.join_path("..").simplify_path
+			var stopper = parentpath / "packages.ini"
+			if not stopper.file_exists then
+				# Recursively get the parent group
+				parent = get_mgroup(parentpath)
+				if parent == null then
+					# Parent is not a group, thus we are not a group either
+					mgroups[rdp] = null
 					return null
 				end
 			end
 		end
 
-		# check parent directory
-		var parentpath = dirpath2.join_path("..").simplify_path
-		var parent = get_mgroup(parentpath)
-
 		var mgroup
 		if parent == null then
-			# no parent, thus new project
-			var mproject = new MProject(pn, model)
-			mgroup = new MGroup(pn, mproject, null) # same name for the root group
-			mproject.root = mgroup
-			toolcontext.info("found project `{mproject}` at {dirpath}", 2)
+			# no parent, thus new package
+			if ini != null then pn = ini["package.name"] or else pn
+			var mpackage = new MPackage(pn, model)
+			mgroup = new MGroup(pn, mpackage, null) # same name for the root group
+			mpackage.root = mgroup
+			toolcontext.info("found package `{mpackage}` at {dirpath}", 2)
+			mpackage.ini = ini
 		else
-			mgroup = new MGroup(pn, parent.mproject, parent)
+			mgroup = new MGroup(pn, parent.mpackage, parent)
 			toolcontext.info("found sub group `{mgroup.full_name}` at {dirpath}", 2)
 		end
 
 		# search documentation
-		# in src first so the documentation of the project code can be distinct for the documentation of the project usage
+		# in src first so the documentation of the package code can be distinct for the documentation of the package usage
 		var readme = dirpath.join_path("README.md")
 		if not readme.file_exists then readme = dirpath.join_path("README")
-		if not readme.file_exists then readme = dirpath2.join_path("README.md")
-		if not readme.file_exists then readme = dirpath2.join_path("README")
 		if readme.file_exists then
 			var mdoc = load_markdown(readme)
 			mgroup.mdoc = mdoc
@@ -471,8 +482,7 @@ redef class ModelBuilder
 		end
 
 		mgroup.filepath = dirpath
-		mgroups[module_absolute_path(dirpath)] = mgroup
-		mgroups[module_absolute_path(dirpath2)] = mgroup
+		mgroups[rdp] = mgroup
 		return mgroup
 	end
 
@@ -497,13 +507,27 @@ redef class ModelBuilder
 		return mdoc
 	end
 
-	# Force the identification of all ModulePath of the group and sub-groups.
-	fun visit_group(mgroup: MGroup) do
+	# Force the identification of all ModulePath of the group and sub-groups in the file system.
+	#
+	# When a group is scanned, its sub-groups hierarchy is filled (see `MGroup::in_nesting`)
+	# and the potential modules (and nested modules) are identified (see `MGroup::module_paths`).
+	#
+	# Basically, this recursively call `get_mgroup` and `identify_file` on each directory entry.
+	#
+	# No-op if the group was already scanned (see `MGroup::scanned`).
+	fun scan_group(mgroup: MGroup) do
+		if mgroup.scanned then return
+		mgroup.scanned = true
 		var p = mgroup.filepath
+		# a virtual group has nothing to scan
+		if p == null then return
 		for f in p.files do
 			var fp = p/f
 			var g = get_mgroup(fp)
-			if g != null then visit_group(g)
+			# Recursively scan for groups of the same package
+			if g != null and g.mpackage == mgroup.mpackage then
+				scan_group(g)
+			end
 			identify_file(fp)
 		end
 	end
@@ -644,11 +668,11 @@ redef class ModelBuilder
 			end
 		end
 
-		# Check for conflicting module names in the project
+		# Check for conflicting module names in the package
 		if mgroup != null then
 			var others = model.get_mmodules_by_name(mod_name)
 			if others != null then for other in others do
-				if other.mgroup!= null and other.mgroup.mproject == mgroup.mproject then
+				if other.mgroup!= null and other.mgroup.mpackage == mgroup.mpackage then
 					var node: ANode
 					if decl == null then node = nmodule else node = decl.n_name
 					error(node, "Error: a module named `{other.full_name}` already exists at {other.location}.")
@@ -686,6 +710,84 @@ redef class ModelBuilder
 		return mmodule
 	end
 
+	# Resolve the module identification for a given `AModuleName`.
+	#
+	# This method handles qualified names as used in `AModuleName`.
+	fun seach_module_by_amodule_name(n_name: AModuleName, mgroup: nullable MGroup): nullable ModulePath
+	do
+		var mod_name = n_name.n_id.text
+
+		# If a quad is given, we ignore the starting group (go from path)
+		if n_name.n_quad != null then mgroup = null
+
+		# If name not qualified, just search the name
+		if n_name.n_path.is_empty then
+			# Fast search if no n_path
+			return search_mmodule_by_name(n_name, mgroup, mod_name)
+		end
+
+		# If qualified and in a group
+		if mgroup != null then
+			# First search in the package
+			var r = mgroup.mpackage.root
+			assert r != null
+			scan_group(r)
+			# Get all modules with the final name
+			var res = r.mmodule_paths_by_name(mod_name)
+			# Filter out the name that does not match the qualifiers
+			res = [for x in res do if match_amodulename(n_name, x) then x]
+			if res.not_empty then
+				if res.length > 1 then
+					error(n_name, "Error: conflicting module files for `{mod_name}`: `{res.join(",")}`")
+				end
+				return res.first
+			end
+		end
+
+		# If no module yet, then assume that the first element of the path
+		# Is to be searched in the path.
+		var root_name = n_name.n_path.first.text
+		var roots = search_group_in_paths(root_name, paths)
+		if roots.is_empty then
+			error(n_name, "Error: cannot find `{root_name}`. Tried: {paths.join(", ")}.")
+			return null
+		end
+
+		var res = new ArraySet[ModulePath]
+		for r in roots do
+			# Then, for each root, collect modules that matches the qualifiers
+			scan_group(r)
+			var root_res = r.mmodule_paths_by_name(mod_name)
+			for x in root_res do if match_amodulename(n_name, x) then res.add x
+		end
+		if res.not_empty then
+			if res.length > 1 then
+				error(n_name, "Error: conflicting module files for `{mod_name}`: `{res.join(",")}`")
+			end
+			return res.first
+		end
+		# If still nothing, just call a basic search that will fail and will produce an error message
+		error(n_name, "Error: cannot find module `{mod_name}` from `{root_name}`. Tried: {paths.join(", ")}.")
+		return null
+	end
+
+	# Is elements of `n_name` correspond to the group nesting of `m`?
+	#
+	# Basically it check that `bar::foo` matches `bar/foo.nit` and `bar/baz/foo.nit`
+	# but not `baz/foo.nit` nor `foo/bar.nit`
+	#
+	# Is used by `seach_module_by_amodule_name` to validate qualified names.
+	private fun match_amodulename(n_name: AModuleName, m: ModulePath): Bool
+	do
+		var g: nullable MGroup = m.mgroup
+		for grp in n_name.n_path.reverse_iterator do
+			while g != null and grp.text != g.name do
+				g = g.parent
+			end
+		end
+		return g != null
+	end
+
 	# Analyze the module importation and fill the module_importation_hierarchy
 	#
 	# Unless you used `load_module`, the importation is already done and this method does a no-op.
@@ -697,61 +799,116 @@ redef class ModelBuilder
 		var stdimport = true
 		var imported_modules = new Array[MModule]
 		for aimport in nmodule.n_imports do
+			# Do not imports conditional
+			var atconditionals = aimport.get_annotations("conditional")
+			if atconditionals.not_empty then continue
+
 			stdimport = false
 			if not aimport isa AStdImport then
 				continue
 			end
-			var mgroup = mmodule.mgroup
-			if aimport.n_name.n_quad != null then mgroup = null # Start from top level
-			for grp in aimport.n_name.n_path do
-				var path = search_mmodule_by_name(grp, mgroup, grp.text)
-				if path == null then
-					nmodule.mmodule = null # invalidate the module
-					return # Skip error
-				end
-				mgroup = path.mgroup
+
+			# Load the imported module
+			var suppath = seach_module_by_amodule_name(aimport.n_name, mmodule.mgroup)
+			if suppath == null then
+				mmodule.is_broken = true
+				nmodule.mmodule = null # invalidate the module
+				continue # Skip error
 			end
-			var mod_name = aimport.n_name.n_id.text
-			var sup = self.get_mmodule_by_name(aimport.n_name, mgroup, mod_name)
+			var sup = load_module_path(suppath)
 			if sup == null then
+				mmodule.is_broken = true
 				nmodule.mmodule = null # invalidate the module
 				continue # Skip error
 			end
+
 			aimport.mmodule = sup
 			imported_modules.add(sup)
 			var mvisibility = aimport.n_visibility.mvisibility
 			if mvisibility == protected_visibility then
+				mmodule.is_broken = true
 				error(aimport.n_visibility, "Error: only properties can be protected.")
+				mmodule.is_broken = true
 				nmodule.mmodule = null # invalidate the module
 				return
 			end
 			if sup == mmodule then
 				error(aimport.n_name, "Error: dependency loop in module {mmodule}.")
+				mmodule.is_broken = true
 				nmodule.mmodule = null # invalidate the module
 			end
 			if sup.in_importation < mmodule then
 				error(aimport.n_name, "Error: dependency loop between modules {mmodule} and {sup}.")
+				mmodule.is_broken = true
 				nmodule.mmodule = null # invalidate the module
 				return
 			end
 			mmodule.set_visibility_for(sup, mvisibility)
 		end
 		if stdimport then
-			var mod_name = "standard"
+			var mod_name = "core"
 			var sup = self.get_mmodule_by_name(nmodule, null, mod_name)
 			if sup == null then
+				mmodule.is_broken = true
 				nmodule.mmodule = null # invalidate the module
 			else # Skip error
 				imported_modules.add(sup)
 				mmodule.set_visibility_for(sup, public_visibility)
 			end
 		end
-		self.toolcontext.info("{mmodule} imports {imported_modules.join(", ")}", 3)
+
+		# Declare conditional importation
+		for aimport in nmodule.n_imports do
+			if not aimport isa AStdImport then continue
+			var atconditionals = aimport.get_annotations("conditional")
+			if atconditionals.is_empty then continue
+
+			var suppath = seach_module_by_amodule_name(aimport.n_name, mmodule.mgroup)
+			if suppath == null then continue # skip error
+
+			for atconditional in atconditionals do
+				var nargs = atconditional.n_args
+				if nargs.is_empty then
+					error(atconditional, "Syntax Error: `conditional` expects module identifiers as arguments.")
+					continue
+				end
+
+				# The rule
+				var rule = new Array[Object]
+
+				# First element is the goal, thus
+				rule.add suppath
+
+				# Second element is the first condition, that is to be a client of the current module
+				rule.add mmodule
+
+				# Other condition are to be also a client of each modules indicated as arguments of the annotation
+				for narg in nargs do
+					var id = narg.as_id
+					if id == null then
+						error(narg, "Syntax Error: `conditional` expects module identifier as arguments.")
+						continue
+					end
+
+					var mp = search_mmodule_by_name(narg, mmodule.mgroup, id)
+					if mp == null then continue
+
+					rule.add mp
+				end
+
+				conditional_importations.add rule
+			end
+		end
+
 		mmodule.set_imported_mmodules(imported_modules)
 
-		# Force standard to be public if imported
+		apply_conditional_importations(mmodule)
+
+		self.toolcontext.info("{mmodule} imports {mmodule.in_importation.direct_greaters.join(", ")}", 3)
+
+		# Force `core` to be public if imported
 		for sup in mmodule.in_importation.greaters do
-			if sup.name == "standard" then
+			if sup.name == "core" then
 				mmodule.set_visibility_for(sup, public_visibility)
 			end
 		end
@@ -769,6 +926,72 @@ redef class ModelBuilder
 		end
 	end
 
+	# Global list of conditional importation rules.
+	#
+	# Each rule is a "Horn clause"-like sequence of modules.
+	# It means that the first module is the module to automatically import.
+	# The remaining modules are the conditions of the rule.
+	#
+	# Each module is either represented by a MModule (if the module is already loaded)
+	# or by a ModulePath (if the module is not yet loaded).
+	#
+	# Rules are declared by `build_module_importation` and are applied by `apply_conditional_importations`
+	# (and `build_module_importation` that calls it).
+	#
+	# TODO (when the loader will be rewritten): use a better representation and move up rules in the model.
+	private var conditional_importations = new Array[SequenceRead[Object]]
+
+	# Extends the current importations according to imported rules about conditional importation
+	fun apply_conditional_importations(mmodule: MModule)
+	do
+		# Because a conditional importation may cause additional conditional importation, use a fixed point
+		# The rules are checked naively because we assume that it does not worth to be optimized
+		var check_conditional_importations = true
+		while check_conditional_importations do
+			check_conditional_importations = false
+
+			for ci in conditional_importations do
+				# Check conditions
+				for i in [1..ci.length[ do
+					var rule_element = ci[i]
+					# An element of a rule is either a MModule or a ModulePath
+					# We need the mmodule to resonate on the importation
+					var m
+					if rule_element isa MModule then
+						m = rule_element
+					else if rule_element isa ModulePath then
+						m = rule_element.mmodule
+						# Is loaded?
+						if m == null then continue label
+					else
+						abort
+					end
+					# Is imported?
+					if not mmodule.in_importation.greaters.has(m) then continue label
+				end
+				# Still here? It means that all conditions modules are loaded and imported
+
+				# Identify the module to automatically import
+				var suppath = ci.first.as(ModulePath)
+				var sup = load_module_path(suppath)
+				if sup == null then continue
+
+				# Do nothing if already imported
+				if mmodule.in_importation.greaters.has(sup) then continue label
+
+				# Import it
+				self.toolcontext.info("{mmodule} conditionally imports {sup}", 3)
+				# TODO visibility rules (currently always public)
+				mmodule.set_visibility_for(sup, public_visibility)
+				# TODO linearization rules (currently added at the end in the order of the rules)
+				mmodule.set_imported_mmodules([sup])
+
+				# Prepare to reapply the rules
+				check_conditional_importations = true
+			end label
+		end
+	end
+
 	# All the loaded modules
 	var nmodules = new Array[AModule]
 
@@ -796,7 +1019,7 @@ class ModulePath
 	# The human path of the module
 	var filepath: String
 
-	# The group (and the project) of the possible module
+	# The group (and the package) of the possible module
 	var mgroup: MGroup
 
 	# The loaded module (if any)
@@ -805,13 +1028,22 @@ class ModulePath
 	redef fun to_s do return filepath
 end
 
+redef class MPackage
+	# The associated `.ini` file, if any
+	#
+	# The `ini` file is given as is and might contain invalid or missing information.
+	#
+	# Some packages, like stand-alone packages or virtual packages have no `ini` file associated.
+	var ini: nullable ConfigTree = null
+end
+
 redef class MGroup
 	# Modules paths associated with the group
 	var module_paths = new Array[ModulePath]
 
 	# Is the group interesting for a final user?
 	#
-	# Groups are mandatory in the model but for simple projects they are not
+	# Groups are mandatory in the model but for simple packages they are not
 	# always interesting.
 	#
 	# A interesting group has, at least, one of the following true:
@@ -821,9 +1053,34 @@ redef class MGroup
 	# * it has a documentation
 	fun is_interesting: Bool
 	do
-		return module_paths.length > 1 or mmodules.length > 1 or not in_nesting.direct_smallers.is_empty or mdoc != null
+		return module_paths.length > 1 or
+			mmodules.length > 1 or
+			not in_nesting.direct_smallers.is_empty or
+			mdoc != null or
+			(mmodules.length == 1 and default_mmodule == null)
 	end
 
+	# Are files and directories in self scanned?
+	#
+	# See `ModelBuilder::scan_group`.
+	var scanned = false
+
+	# Return the modules in self and subgroups named `name`.
+	#
+	# If `self` is not scanned (see `ModelBuilder::scan_group`) the
+	# results might be partial.
+	fun mmodule_paths_by_name(name: String): Array[ModulePath]
+	do
+		var res = new Array[ModulePath]
+		for g in in_nesting.smallers do
+			for mp in g.module_paths do
+				if mp.name == name then
+					res.add mp
+				end
+			end
+		end
+		return res
+	end
 end
 
 redef class SourceFile