tcd: Determine correct scope from user input

If a user specifies both {window} and {tab}, `getcwd()`/`haslocaldir()`
are using "tab" as the scope that should be reported.  However, it
should be using "window" as the scope, within the specified tab page.

src/nvim/eval.c

@@ -9888,7 +9888,7 @@ static void f_getcmdwintype(typval_T *argvars, typval_T *rettv)
 static void f_getcwd(typval_T *argvars, typval_T *rettv)
 {
   // Possible scope of working directory to return.
-  CdScope scope = MIN_CD_SCOPE;
+  CdScope scope = kCdScopeInvalid;
 
   // Numbers of the scope objects (window, tab) we want the working directory
   // of. A `-1` means to skip this scope, a `0` means the current object.
@@ -9917,26 +9917,27 @@ static void f_getcwd(typval_T *argvars, typval_T *rettv)
       return;
     }
     scope_number[i] = argvars[i].vval.v_number;
-    // The scope is the current iteration step.
-    scope = i;
     // It is an error for the scope number to be less than `-1`.
     if (scope_number[i] < -1) {
       EMSG(_(e_invarg));
       return;
     }
+    // Use the narrowest scope the user requested
+    if (scope_number[i] >= 0 && scope == kCdScopeInvalid) {
+      // The scope is the current iteration step.
+      scope = i;
+    } else if (scope_number[i] < 0) {
+      scope = i + 1;
+    }
   }
 
-  // Normalize scope, the number of the new scope will be 0.
-  if (scope_number[scope] < 0) {
-    // Arguments to `getcwd` always end at second-highest scope, so scope will
-    // always be <= `MAX_CD_SCOPE`.
-    scope++;
+  // If the user didn't specify anything, default to window scope
+  if (scope == kCdScopeInvalid) {
+    scope = MIN_CD_SCOPE;
   }
 
   // Find the tabpage by number
-  if (scope_number[kCdScopeTab] == -1) {
-    tp = NULL;
-  } else if (scope_number[kCdScopeTab] > 0) {
+  if (scope_number[kCdScopeTab] > 0) {
     tp = find_tabpage(scope_number[kCdScopeTab]);
     if (!tp) {
       EMSG(_("E5000: Cannot find tab number."));
@@ -9945,10 +9946,8 @@ static void f_getcwd(typval_T *argvars, typval_T *rettv)
   }
 
   // Find the window in `tp` by number, `NULL` if none.
-  if (scope_number[kCdScopeWindow] == -1) {
-    win = NULL;
-  } else if (scope_number[kCdScopeWindow] >= 0) {
-    if (!tp) {
+  if (scope_number[kCdScopeWindow] >= 0) {
+    if (scope_number[kCdScopeTab] < 0) {
       EMSG(_("E5001: Higher scope cannot be -1 if lower scope is >= 0."));
       return;
     }
@@ -9989,6 +9988,9 @@ static void f_getcwd(typval_T *argvars, typval_T *rettv)
         }
       }
       break;
+    case kCdScopeInvalid:
+      // We should never get here
+      assert(false);
   }
 
   if (from) {
@@ -10836,7 +10838,7 @@ static void f_has_key(typval_T *argvars, typval_T *rettv)
 static void f_haslocaldir(typval_T *argvars, typval_T *rettv)
 {
   // Possible scope of working directory to return.
-  CdScope scope = MIN_CD_SCOPE;
+  CdScope scope = kCdScopeInvalid;
 
   // Numbers of the scope objects (window, tab) we want the working directory
   // of. A `-1` means to skip this scope, a `0` means the current object.
@@ -10861,25 +10863,26 @@ static void f_haslocaldir(typval_T *argvars, typval_T *rettv)
       return;
     }
     scope_number[i] = argvars[i].vval.v_number;
-    // The scope is the current iteration step.
-    scope = i;
     if (scope_number[i] < -1) {
       EMSG(_(e_invarg));
       return;
     }
+    // Use the narrowest scope the user requested
+    if (scope_number[i] >= 0 && scope == kCdScopeInvalid) {
+      // The scope is the current iteration step.
+      scope = i;
+    } else if (scope_number[i] < 0) {
+      scope = i + 1;
+    }
   }
 
-  // Normalize scope, the number of the new scope will be 0.
-  if (scope_number[scope] < 0) {
-    // Arguments to `haslocaldir` always end at second-highest scope, so scope
-    // will always be <= `MAX_CD_SCOPE`.
-    scope++;
+  // If the user didn't specify anything, default to window scope
+  if (scope == kCdScopeInvalid) {
+    scope = MIN_CD_SCOPE;
   }
 
   // Find the tabpage by number
-  if (scope_number[kCdScopeTab] == -1) {
-    tp = NULL;
-  } else if (scope_number[kCdScopeTab] > 0) {
+  if (scope_number[kCdScopeTab] > 0) {
     tp = find_tabpage(scope_number[kCdScopeTab]);
     if (!tp) {
       EMSG(_("5000: Cannot find tab number."));
@@ -10888,10 +10891,8 @@ static void f_haslocaldir(typval_T *argvars, typval_T *rettv)
   }
 
   // Find the window in `tp` by number, `NULL` if none.
-  if (scope_number[kCdScopeWindow] == -1) {
-    win = NULL;
-  } else if (scope_number[kCdScopeWindow] >= 0) {
-    if (!tp) {
+  if (scope_number[kCdScopeWindow] >= 0) {
+    if (scope_number[kCdScopeTab] < 0) {
       EMSG(_("E5001: Higher scope cannot be -1 if lower scope is >= 0."));
       return;
     }
@@ -10918,6 +10919,9 @@ static void f_haslocaldir(typval_T *argvars, typval_T *rettv)
       // The global scope never has a local directory
       rettv->vval.v_number = 0;
       break;
+    case kCdScopeInvalid:
+      // We should never get here
+      assert(false);
   }
 }
 

src/nvim/ex_docmd.c

@@ -6865,6 +6865,9 @@ void post_chdir(CdScope scope)
       curwin->w_localdir = vim_strsave(NameBuff);
     }
     break;
+  case kCdScopeInvalid:
+    // We should never get here
+    assert(false);
   }
 
   shorten_fnames(TRUE);

src/nvim/ex_docmd.h

@@ -26,6 +26,7 @@
 /// `getcwd()`. When using scopes as limits (e.g. in loops) don't use the scopes
 /// directly, use `MIN_CD_SCOPE` and `MAX_CD_SCOPE` instead.
 typedef enum {
+  kCdScopeInvalid = -1,
   kCdScopeWindow,  ///< Affects one window.
   kCdScopeTab,     ///< Affects one tab page.
   kCdScopeGlobal,  ///< Affects the entire instance of Neovim.