More detailed error messages

+bids/+util/tsvread.m

@@ -19,7 +19,7 @@
 %-Check input arguments
 %--------------------------------------------------------------------------
 if ~exist(f,'file')
-    error('Unable to read file ''%s''',f);
+    error('Unable to read file ''%s'': file not found',f);
 end
 
 if nargin < 2, v = ''; end
@@ -46,17 +46,20 @@
         sts = true;
         try
             x   = tsvread(fz{1});
-        catch
+        catch err
             sts = false;
+            err_msg = err.message;
         end
         delete(fz{1});
         rmdir(fileparts(fz{1}));
-        if ~sts, error('Cannot load ''%s''.',f); end
+        if ~sts
+            error('Cannot load file ''%s'': %s.',f,err_msg);
+        end
     otherwise
         try
             x = load(f);
         catch
-            error('Unknown file format.');
+            error('Cannot read file ''%s'': Unknown file format.',f);
         end
 end
 
@@ -80,7 +83,8 @@
             try
                 x = x.(fn{v});
             catch
-                error('Invalid data index.');
+                error('Data index out of range: %d (data contains %d fields)',...
+                    v,numel(fn));
             end
         end
     end
@@ -89,10 +93,12 @@
         try
             x = x(:,v);
         catch
-            error('Invalid data index.');
+            error('Data index out of range: %d (data contains $d columns).',...
+                v,size(x,2));
         end
     elseif ~isempty(v)
-        error('Invalid data index.');
+        error('Invalid data index. When data is numeric, index must be numeric or empty; got a %s',...
+            class(v));
     end
 end
 
@@ -153,7 +159,10 @@
 else
     d = {[]};
 end
-if rem(numel(d{1}),N), error('Varying number of delimiters per line.'); end
+if rem(numel(d{1}),N)
+    error('Invalid DSV file ''%s'': Varying number of delimiters per line.',...
+        f);
+end
 d = reshape(d{1},N,[])';
 allnum = true;
 for i=1:numel(var)

+bids/layout.m

@@ -26,10 +26,9 @@
         BIDS = root; % or BIDS = bids.layout(root.root);
         return;
     else
-        error('Invalid syntax.');
+        error('Invalid input: root must be a char filename or a BIDS struct; got a %s',...
+            class(root));
     end
-else
-    error('Too many input arguments.');
 end
 
 %-BIDS structure
@@ -47,21 +46,26 @@
 %-Validation of BIDS root directory
 %==========================================================================
 if ~exist(BIDS.dir,'dir')
-    error('BIDS directory does not exist.');
+    error('BIDS directory does not exist: ''%s''',BIDS.dir);
 elseif ~exist(fullfile(BIDS.dir,'dataset_description.json'),'file')
-    error('BIDS directory not valid: missing dataset_description.json.');
+    error('BIDS directory not valid: missing dataset_description.json: ''%s''',...
+        BIDS.dir);
 end
 
 %-Dataset description
 %==========================================================================
 try
     BIDS.description = bids.util.jsondecode(fullfile(BIDS.dir,'dataset_description.json'));
-catch
-    error('BIDS dataset description could not be read.');
+catch err
+    error('BIDS dataset description could not be read: %s',err.message);
 end
-if ~isfield(BIDS.description,'BIDSVersion') || ~isfield(BIDS.description,'Name')
-    error('BIDS dataset description not valid.');
+if ~isfield(BIDS.description,'BIDSVersion')
+    error('BIDS dataset description not valid: missing BIDSVersion field');
 end
+if ~isfield(BIDS.description,'Name')
+    error('BIDS dataset description not valid: missing Name field');
+end
+
 % See also optional README and CHANGES files
 
 %-Optional directories

+bids/private/file_utils.m

@@ -47,7 +47,7 @@
             case 'fpath'
                 str{n} = fileparts(char(cpath(str(n))));
             otherwise
-                error('Unknown option.');
+                error('Unknown option: ''%s''',options{1});
         end
     end
     options = {};
@@ -186,7 +186,7 @@
     case 'fplist'
         fp = true;
     otherwise
-        error('Invalid syntax.');
+        error('Invalid action: ''%s''.',action);
 end
 if nargin < 2
     d = pwd;

+bids/private/parse_filename.m

@@ -50,7 +50,7 @@
     try
         p = orderfields(p,['filename','ext','type',fields]);
     catch
-        warning('Ignoring file "%s" not matching template.',filename);
+        warning('Ignoring file ''%s'' not matching template.',filename);
         p = struct([]);
     end
 end

+bids/query.m

@@ -16,10 +16,7 @@
 % Copyright (C) 2016-2018, Guillaume Flandin, Wellcome Centre for Human Neuroimaging
 % Copyright (C) 2018--, BIDS-MATLAB developers
 
-
-if nargin < 2
-    error('Not enough input arguments.');
-end
+narginchk(2,Inf);
 
 BIDS = bids.layout(BIDS);
 
@@ -147,7 +144,7 @@
                 result(cellfun('isempty',result)) = [];
         end
     otherwise
-        error('Unable to perform BIDS query.');
+        error('Invalid query input: ''%s''', query);
 end
 
 

tests/bids_runtests.m

@@ -38,9 +38,8 @@
         fprintf('%s',d(i).name(1:end-2));
         feval(d(i).name(1:end-2));
         results(i).Passed = true;
-    catch
+    catch err
         results(i).Failed = true;
-        err = lasterror;
         fprintf('\n%s',err.message);
     end
 

tests/test_bids_examples.m

@@ -30,10 +30,9 @@ function test_bids_examples(pth)
         BIDS = bids.layout(fullfile(pth,d(i).name));
         sts(i) = true;
         fprintf('.');
-    catch
+    catch err
         fprintf('X');
-        le = lasterror;
-        msg{i} = le.message;
+        msg{i} = err.message;
     end
 end
 fprintf('\n');